Example 1: Volume of revolution in 2017 alevel P2 4b
Let a=2 so we can visualise the shape of the graph
Example 2: Solution curve for Differential equation. 2014 alevel P1
This is solution for part iv.
It can be sketched without expressing the solution in the form x=f(t)
DHS J1 2018 Aug Test
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.
2011 alevel P1 Q11
Suppose we want to sketch the graph from -3 to 8.
- 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.
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
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.
GC can be used to check the solution to differential equation.
Example from 2014 P1 Q10
Suppose we want to check whether the following solution to 10 iv is correct:
Enter the following in GC
Since Y2 and Y3 gave the same values, the solution is correct.
Enter the data in the GC as follows:
Variance can also calculated using the GC as follows:
RI 2018 J2 MYE Q13i
Method 1: Change Xres to 3
The Xres button refers to pixel resolution (1 through 8). At Xres = 1, functions are evaluated and graphed at each pixel on the x-axis. At Xres = 8, functions are evaluated and graphed at every eighth pixel along the x-axis. Small Xres values improve graph resolution but may cause the calculator to draw graphs more slowly. Setting Xres to 3 provides good balance between speed and resolution.
Time taken to plot= 23.4 s
Time taken to plot= 3.6 s
Savings of almost 20 seconds! Which is crucial in exams
Method 2: Turn off “Detect Asymptotes”
The following example illustrates how we can use GC in Differential equations, and avoid the need to do integration to solve differential equation.
Solution for part ii
A room contains n randomly chosen people. Assume that a randomly chosen person is equally likely to have been born on any day of the 365 days in a year. Find the smallest value of n such that the people in the room were all born on different days of the year is less than 0.5.
Using TI 84 Plus (OS 2.55)
Therefore, smallest value of n =23