Question

E(x)=(2x-3)la puterea a2-a  - (x+1)la puterea a2-a. Se cere E(1 supra 2 ) : E(-1 supra 2 ) = ?

Answer 1

Aplic formula a²-b²=(a-b)*(a+b)
E(x)=(2x-3)²-(x+1)²=(2x-3-x-1)(2x-3+x+1)=(x-4)(3x-2)

E(1/2)=(1/2-4)(3*1/2-2)=(1-2*4)*(3-2*2)/2=7/2
E(-1/2)=(-1/2-4)(-3/2-2)=(-1-4*2)(-3-2*2)/2=63/2
E(1/2):E(-1/2)=7/2*2/63=1/9