Which of the following is a perfect square trinomial? a. x2 + 10x + 25
b. x2 + 5x + 10
c. XP + 10x + 20
d. x2 + 10x + 50

Find the solution of system of equation y= x-4 y=4x+2

Which of the following pairs of functions are inverses of each other? o a. f(x)=x72+8 and 96-9 = 7/x+2) =8 o b. f(x)= 6(x - 2)+3 and g(x) - *#2-3 o c. $4) = 5(2)-3 and 90- 4*: 73 o d. f(x) = 6)-12 and 910 – +12

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .