Multiply (t+1)(t-2) Simplify your answer?

t² - t - 2 by inspection

t^2 - t - 2

(t + 1)(t - 2)
= t(t) - t(2) + 1(t) - 1(2)
= t^2 - 2t + t - 2
= t^2 - t - 2

All you need to do is remember that t + 1 and t - 2 represent two different numbers, whatever t may be. When multiplying the two together you must multiply it like so:
(t + 1) (t - 2)
= t^2 - 2t + 1t - 2 [You can test this out by substituting numbers in. A lot of people go wrong when they do this: (t + 1) (t - 2) = t^2 - 2. This is wrong. You can verify that by substitution as well.]
Then, you need to group "like terms" together.
= t^2 - 1t - 2 [1t can be written as t]
= t^2 - t - 2
This is your answer.

Hope this helps.

(t+1)(t-2)
=t(t-2) + 1(t-2)
=t^2 - 2t + t - 2
=t^2 - t - 2(quadratic equation)
=t^2 - 2t + t - 2
=t(t-2) + 1 (t-2)
=(t+1),(t-2)

(t+1)(t-2)
F: t * t = t^2
O: t * -2 = -2t
I: 1 * t = t
L: 1 * -2 = -2

= t^2 - 2t + t - 2
= t^2 - t - 2