Question

Va rog ajutati-ma!!
Este urgent!!

Answer 1

Răspuns:

Explicație pas cu pas:

a) 2(3x - 2) - 4(4 - 2x) = 6x - 4 - 16 + 8x = 14x - 20

b) 3(1 - 5x) - 2(2x - 1) = 3 - 15x - 4x + 2 = 5 - 19x

c) (x - 2y)(2x + y) = 2x^2 + xy - 4xy - 2y^2 = 2x^2 - 3xy - 2y^2

d) (x + 3)(4x - 1) = 4x^2 - x + 12x - 3 = 4x^2 + 11x - 3

e) (x - 2)(2x + 1) - (2x + 3)(1 - 3x) = 2x^2 + x - 4x - 2 - (2x - 6x^2 + 3 - 9x) =

=2x^2 + x - 4x - 2 - 2x + 6x^2 - 3 + 9x = 8x^2 + 4x - 5

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

g) (2x + 1)^2 - (1 - 2x)^2 = 4x^2 + 4x + 1 - (1 - 4x + 4x^2) = 4x^2 + 4x + 1 - 1 + 4x - 4x^2 = 8x

h) (x^2 - x + 1)(x^2 + x + 1) = x^4 + x^3 + x^2 -x^3 - x^2 - x + x^2 + x + 1 =

=x^4 + x^2 + 1