# Tips & Challenges

## How to sketch both cartesian and parametric graphs on the same diagram using GC

Example Suppose we want to sketch the curve C and the line y=-2x+2 on the same graph Note how the line y-2x+2 is entered. Adjust the Tmax to 1%  more so the graph displays correctly. ## Finding sequence of transformation

Usually the sequence of transformation can be found by the replacement method. However, it can be tough to find the replacement for complicated functions. For such cases, we can use the general linear transformation c f(bx+a)+d to find the sequence.

cf(bx+a)+d = Translate by a units in the negative X direction, then scale by a factor of 1/b parallel to the X-axis, then scale by a factor of c parallel to the Y-axis, then translate by d units in the positive Y direction.

Example Solution ## Sketching Periodic functions with GC Suppose we want to sketch the graph from -3 to 8.

1. Enter by pressing “Math, Piecewise”. 2. Adjust the window setting to the required domain. 3. Trace the end point at -3 since it is not 1 complete cycle. ## An interesting relationship between two discrete random variables associated with a die  ## Functional differences between TI 84 Plus CE and TI 84 Plus C for h2 maths

The following comparison are based on

TI 84 CE: Operating system 5.3.0

TI 84 Plus C: Operating system 4.2

Singapore Approved Operating System

• Division of complex numbers in TI 84 Plus CE can be entered in fractions, whereas it must be entered using division in TI 84 Plus C

. • Piecewise function is now available in TI 84 Plus CE. This command can be found under MATH B: piecewise ( . Piecewise function can also be created manually in TI 84 Plus C but slightly more tedious. New CONDITIONS submenu in “2nd test” allows faster entry of intervals for the piecewise functions • Inverse binomial distribution and inverse norm enhancement in TI 84 CE  • Store tangent and faster access to n/d template in TI 84 CE Conclusion

There are no major functional differences between TI 84 Plus CE and TI 84 Plus C. For piecewise functions, students should learn how to sketch manually without using the GC.

## Using GC to calculate Expectation and Variance of Discrete Random Variable

Example 1 Solution

Enter the data in the GC as follows:     Variance can also calculated using the GC as follows:   Example 2  