Question

Let z(t)= 2t^2 +7t -4, find z(-1) and z(2).

Answer 1

Let z(t) be the function:

$z(t)=2t^2+7t-4$

Then, to find z(-1), we evaluate directly into the function like this:

$z(-1)=2(-1)^2+7(-1)-4=2(1)-7-4=2-11=-9$

and we do the same thing for z(2):

$z(2)=2(2)^2+7(2)-4=8+14-4=18$

therefore, z(-1)=-9 and z(2)=18