Question

F(x) = { -2x -1, x ≤ 2

{ -x +4, x > 2


what do I do here?
I also have a graphing calculator, I would also like to know how to put it in the calculator. TI 84 plus. thank you!!

Answer 1

Use the appropriate entry method for piecewise functions for the graphing calculator of interest.

Explanation:

For Desmos, the entry looks like ...

f(x) = {x ≤ 2: -2x-1,-x+4}

_____

For a TI-84 calculator, the entry may look like ...

Y₁ = (-2X–1)(X≤2) + (-X+4)(X>2)

The symbols ≤ and > come from the TEST menu, which is the (2nd) shift of the MATH key.

Note that the function is the sum of the pieces, each piece multiplied by a test. For something like 0≤x<2, the multiplier would be a pair of tests:

... (0≤X)(X<2)