Question

cât de repede se poate a nevoi urgent 3 4 5 6

Answer 1

Răspuns

Explicație pas cu pas:

3

x^2 + 2x + 1 = (x + 1)^2

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

[(x + 1)^2 / 2(x + 1)(x - 1)] * 2x / (x + 1) = x / (x - 1)

________

4

10/3x - x/3 + 5/x = 10/3x - x^2/3x + 15/3x = (25 - x^2)/3x = (5 - x)(5 + x)/3x

__________

5

x^2 - 4 = (x - 2)(x + 2)

(x - 2)(x + 2)*x (x + 2) / (x + 2)^2 * x(x - 2) = [x(x - 2)(x + 2)^2] / [x(x - 2)(x + 2)^2] = 1

_________

6

x/(x + 1) - (x+1)/x - 1/x(x + 1) = x^2/x(x + 1) - (x + 1)^2/x(x + 1) - 1/x(x + 1) =

[x^2 - (x^2 + 2x + 1) - 1] / x(x + 1) = (x^2 - x^2 - 2x - 1 - 1) / x(x + 1) = -2x/x(x + 1) = -2/(x + 1)