Question

fie E(X) =(2x+1)^2-3(x+1)-(x-1))x+1)+6(x-1), aratati ca E(x) =4x-7​

Answer 1

Răspuns:

$e(x) = {(2x + 1})^{2} - 3(x + 1) - (x - 1)(x + 1) + 6(x - 1) \\ e(x) = ( {2x})^{2} + 2 \times 2x \times 1 + {1}^{2} - 3x - 3 - ( { {x}^{2} } - {1}^{2} ) + 6x - 6 \\ e(x) = 4 {x}^{2} + 4x + 1 - 3x - 3 - {x}^{2} + 1 + 6x - 6 \\ e(x) = 3 {x}^{2} + 7x - 7$

Nu da 4x-7 posibil sa fi scris tu expresia greșit

Answer 2

E(x)=(2x+1)²-3(x+1)²-(x-1)(x+1)+6(x-1)

E(x)=4x²+4x+1-3(x²+2x+1)-(x²-1)+6x-6

E(x)=4x²+4x+1-3x²-6x-3-x²+1+6x-6

E(x)=4x-7