When you are working on problems in the mathematical chapters, you can refer to this chapter for extra help with your GDC if you need it. Instructions for the Casio fx-9860GIl calculator Use this list to help you fi nd the topic you need Table of contents...
Casio fx-9860GII Before you start You should be familiar with: Important keys on the keyboard: SHIF T DEL MENU ● X,i,T OPTN EXIT For a reminder of how to ● The home screen perform the basic operations ● Using the Main Menu to enter the mode you want have a look at your GDC manual.
Casio fx-9860GII Finding information about the graph The GDC can give you a lot of information about the graph of a function, such as the coordinates of points of interest and the gradient (slope). 1.2 Finding the gradient (slope) of a line The correct mathematical notation for gradient (slope) is .
Casio fx-9860GII To draw graphs y = 10 − 2x and y = x − 2: Press MENU and choose 5: GRAPH and press The default graph type is Function, so the form Y= is displayed. Type 10 – 2x and press and x –...
Casio fx-9860GII Choose equations in two unknowns and press Note: This is how you will use the linear equation solver in your examinations. In your project, you might want to solve a more complicated system with more equations and more variables.
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Casio fx-9860GII Example 5 Solve the equations 2x − 3y + 4z = 1 x − y − z = −1 −x + 2y − z = 2 Press MENU . You will see the dialog box as shown on the right.
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Casio fx-9860GII Example 6 Solve the equations 2x + 4y + 2z = 8 x + 2y + z = 4 3x − y + z = −9 Press MENU . You will see the dialog box as shown on the right.
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Casio fx-9860GII Type the coeffi cients from the three equations into the matrix, pressing after each number. Press The reduced row echelon form gives the solutions to the equations of the line if the fi nal row of the matrix is all zeroes.
Casio fx-9860GII The GDC solves the equations by an inverse matrix method. In this example there is an error because the matrix is singular, which means that there will be no unique solution. To fi nd the solution you can use the reduced row echelon form method instead.
Casio fx-9860GII Adjust the window to make the exponential curve fi t the screen better. For help with changing axes, see your GDC manual. 1.7 Solving quadratic equations When solving quadratic equations in an examination, you do not need to show any method of solution.
Casio fx-9860GII 1.8 Finding a local minimum or maximum point Example 10 Find the minimum point on the graph of y = x − 2x + 3. Draw the graph of y = x − 2x + 3 (See Example 8).
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Casio fx-9860GII OPTN Press GLINK. When you scroll through the table the cross moves along the curve. The minimum value shown in the table is 2 when x = 1. Look more closely at the values of the function around x = 1.
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Casio fx-9860GII Example 11 Find the maximum point on the graph of y = −x + 3x − 4. Press MENU and choose 5: GRAPH and press The default graph type is Function, so the form Y = is displayed.
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Casio fx-9860GII Press to view the table. Press G·CON to display the graph alongside the table. OPTN Press GLINK. When you scroll through the table the cross moves along the curve. The minimum value shown in the table is –2 when x = 1 and x = 2.
Casio fx-9860GII The calculator displays the maximum point on the curve at (1.5, −1.75). Complex numbers 1.9 Operations with complex numbers Example 12 Evaluate the following expressions − (2 + 3i ) ⋅ (3 − 4i ) − (1 − i )
Casio fx-9860GII 1.10 Conjugate, modulus and argument Example 13 Let z z ∗ Find arg (z) Press MENU . You will see the dialog box as shown on the right. Choose 1: RUN·MAT and press OPTN Press CPLX | Conj Enter the complex number in brackets.
Casio fx-9860GII From the menu, choose Polynomial and press If there are previous equations in the memory, EXIT press until you return to this menu. You will see the dialog box as shown on the right. Choose equations of degree 3 and press Another dialog box opens for you to enter the equation.
Casio fx-9860GII a b / c ∠ π Enter SHIF T SHIF T and then press OPTN CPLX | a + bi Press The ∠ symbol is above the X,i,T You can also change the mode that the calculator uses to display complex results in settings.
Casio fx-9860GII 1.14 Finding a horizontal asymptote Example 17 Find a horizontal asymptote to the graph of y = 3 + 2. Draw the graph of y = 3 + 2 (See Example 16). You can look at a table of the values of the function.
Casio fx-9860GII Press OPTN GLINK. As the value of x gets smaller, Y gets closer and closer to 2. Press EXIT and then press SET. Change the minimum value of x to –12. OPTN G·CON GLINK. Eventually the value of Y displayed in the table reaches 2.
Casio fx-9860GII 1.16 Finding an inverse function The inverse of a function can be found by interchanging the x and y values. Geometrically this can be done by refl ecting points in the line y = x. Example 19 Show that the inverse of the function y = 10 is y = log x by refl...
Casio fx-9860GII 1.17 Drawing a logarithmic graph Example 20 Draw the graph of y = 2log x + 3. Press MENU . You will see the dialog box as shown on the right. Choose 5: GRAPH and press X,i,T Press...
Casio fx-9860GII 1.19 Drawing trigonometric graphs Example 22 Draw the graph of 2sin Press MENU . You will see the dialog box as shown on the right. Choose 5: GRAPH and press 2sin Type and press X,i,T Press SHIF T...
Casio fx-9860GII More complicated functions 1.20 Solving a combined quadratic and exponential equation To solve the equation, fi nd the point of intersection between the quadratic function y − 2x + 3 and the exponential function = 3 × 2 −x...
Casio fx-9860GII Sequences and series 1.21 Summation of a series Example 24 Find the sum of the fi rst 20 terms of the arithmetic sequence 4, 7, 10, 13, … The kth term of an arithmetic sequence is u + (k − 1)d In this example u = 4, d = 3 and n = 20.
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Casio fx-9860GII Example 26 + ... are needed before their sum exceeds 5.5? How many terms of the series 2 1 = 2, r = In the example u and n is to be found. − ⎛ ⎞ ∑ ⋅...
Casio fx-9860GII Modelling 1.22 Using sinusoidal regression x, cos x, tan x, … is a mathematical convention that has little algebraic The notation sin meaning. To enter these functions on the GDC, you should enter (sin(x)) , etc. However, the...
Casio fx-9860GII 1.23 Drawing a piecewise function Example 28 ì ï 4 +3, ï ï í Draw the function ï ï ï î Press MENU . You will see the dialog box as shown on the right. Choose 5: GRAPH and press The default graph type is Function, so the form Y= is displayed.
Casio fx-9860GII Adjust the window to make the cubic curve fi t the screen better. For help with changing axes, see your GDC manual. Press SHIF T (SET UP). Set Derivative to On. Press DRAW to return to the graph.
Casio fx-9860GII Press Sketch. Press Tang. The calculator displays the trace screen. (–) Press Press The equation of the tangent is y = −3.25x + 5.75. 2.3 Finding maximum and minimum points Example 31 Find the local maximum and local minimum points on the cubic curve.
Casio fx-9860GII SHIF T Press G-Solv. Press MIN to fi nd the minimum point. The calculator displays the local minimum at the point (2.23, −7.24). 2.4 Finding a numerical derivative Using the calculator it is possible to fi nd the numerical value of any derivative for any value of x.
Casio fx-9860GII 2.5 Graphing a numerical derivative Although the calculator can only evaluate a numerical derivative at a point, it will graph the gradient function for all values of x. Example 33 If y , draw the graph of MENU Press .
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Casio fx-9860GII Example 34 − Find the values of x on the curve y 1 where the gradient is 3. MENU Press . You will see the dialog box as shown on the right. Choose 5: GRAPH and press Press CALC.
Casio fx-9860GII Press to select the second point. The GDC shows a point of intersection at (2, 3). The curve has gradient 3 when x = –4 and x = 2. 2.6 Using the second derivative The calculator can fi nd fi rst and second derivatives. The second derivative can be used to determine whether a point is a maximum or minimum point.
Casio fx-9860GII Press OPTN CALC | to enter the second derivative template. Enter Y1 in the template as the function using the same procedure to enter the Y. Enter the value of x as 0. Repeat for the second derivative when x = 3.
Casio fx-9860GII Enter the upper and lower limits, the function and x in the template. Press The value of the integral is 21.5 (to 3 sf ). 3.2 Finding the area under a curve Example 37 y = 3x − 5 Find the area bounded by the curve, the x-axis and the lines x = –1 and x = 1.
Since the area lies below the x-axis in this case, the integral is negative. 4 Vectors There is no scalar product function on the Casio GDC, Scalar product but you can fi nd the result by multiplying the vectors 4.1 Calculating a scalar product as lists and then fi nding the sum of the terms in the list.
Casio fx-9860GII Press OPTN LIST | Sum. Enter the vectors as lists using curly brackets { }. Separate the terms of the vectors using commas. Multiply the two vector lists together. Close the bracket and press ENTER ⎛ ⎞ ⎛...
The angle between 2 Vector product 4.3 Calculating a vector product The Casio fx-9860GII does not have the ability to perform cross products of vectors. 5 Statistics and probability You can use your GDC to draw charts to represent data and to calculate basic statistics such as mean, median, etc.
Casio fx-9860GII 5.2 Entering data from a frequency table Example 41 Number 1 2 3 4 5 Enter the data in the table: Frequency 3 4 6 5 2 MENU Press . You will see the dialog box as shown on the right.
Casio fx-9860GII Press (Trace). SHIF T Use the key to move to each of the bars and display their value and frequency. You should now see a frequency histogram for the data in the list 1, 1, 3, 9, 2.
Casio fx-9860GII 5.5 Drawing a box and whisker diagram from a list Example 44 Draw a box and whisker diagram for this data: 1, 1, 3, 9, 2. Enter the data in List 1 (see Example 40). Press GRPH and SET.
Casio fx-9860GII Press SHIF T (Trace). Use the key to move the cursor over the plot to see the quartiles, Q1 and Q3, the median and the maximum and minimum values. Calculating statistics You can calculate statistics such as mean, median, etc. from a list, or from a frequency table.
Casio fx-9860GII 5.8 Calculating statistics from a frequency table Example 47 Calculate the summary statistics for this data: Number 1 2 3 4 5 Frequency 3 4 6 5 2 Enter the data in List 1 and List 2 (see Example 41).
Casio fx-9860GII 5.9 Calculating the interquartile range Example 48 Calculate interquartile range for this data: The interquartile range is the Number 1 2 3 4 5 difference between the upper Frequency and lower quartiles (Q − Q 3 4 6 5 2...
Casio fx-9860GII Calculating binomial probabilities 5.11 The use of nCr Example 50 ⎛ ⎞ Find the value of ⎜ ⎟ ⎝ ⎠ MENU Press . You will see the dialog box as shown on the right. Choose 1: RUN·MAT and press Press PROB to enter probability menu.
Casio fx-9860GII 5.12 Calculating binomial probabilities Example 52 X is a discrete random variable and X ~ Bin(9, 0.75). Calculate P(X = 5) ⎛ ⎞ P X = 0 75 0 25 ⎝ ⎜ ⎠ ⎟ The calculator can fi nd this value directly.
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Casio fx-9860GII Enter the values 0,1,2,3,4,5,6,7 in List1. Press after each number. Press DIST | BINM | Bpd. Press List. Choose List1. Enter the number of trials, 7 and the probability 0.3. Press The calculator displays each of the probabilities.
Casio fx-9860GII When using the lower bound probability to calculate other probabilities, it is easier to do this without the wizard. MENU Press . Choose 1: RUN·MAT and press P(5 ≤ X ≤ 15) = P(X ≤ 15) – P(X ≤ 4)
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Casio fx-9860GII The calculator shows that P(X = 2 ) = 0.0758 (to 3 sf) − × − × − × ( . ) ( . ) ( . ) ≤ The calculator can fi nd this value directly. Press...
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If X ~ Po( μ ) fi nd the value of μ , correct to 3 decimal places, given that P(X = 2) = 0.035. There is no inverse Poisson function on the Casio fx-9860GII, so instead you should use the numerical solver function to fi nd a value of μ when you are given a probability.
Casio fx-9860GII The required value of μ is 0.309 (to 3 sf). Calculating normal probabilities 5.14 Calculating normal probabilities from X-values Example 57 A random variable X is normally distributed with a mean of 195 and a standard deviation of 20 or x ~ N(195, 20) .
Casio fx-9860GII P(X < 190) = 0.401 (to 3 sf) P(x > 194) Press EXIT to return to the entry screen. Enter Lower Bound as 194, Upper Bound as 1E99, σ as 20 and μ as 195. P(X > 194) = 0.520 (to 3 sf) P(187 <...
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Casio fx-9860GII Example 58 A random variable X is normally distributed with a mean of 75 and a standard You are given a lower- deviation of 12 or X ~ N(75, 12 ). If P (X < x) = 0.4, fi nd the value of x.
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Casio fx-9860GII Press DIST NORM InvN to use the Inverse Normal function. Press Var. You should enter the values: Area (probability), σ and μ , in order. ), Area as 0.2, σ as 12 and μ as 75. Enter Tail as Right ( Press So if P (X >...