Question

Me ajudem presiso pra pasar de ano

Answer 1

Resposta:

$a)(5x-1) \ . \ (5x+1)\\\\=(5x)^2-1^2\\\\=25x^2-1$

$b)(a+b) \ . \ (a+b)\\\\=a+b\\\\=(a+b)^2$

$c)(2x^{2} -3x-6) \ . \ (5x-2)\\\\=2x^2 \ . \ 5x+2x^2(-2)-3x \ . \ 5x-3x(-2)-6 \ . \ 5x-6(-2)\\\\=10x^3-19x^2-24x+12$

$d)(2a+\frac{3}{5} b) \ . \ (a-\frac{1}{2} b)\\\\=\frac{10a+3b}{5} (a-\frac{1}{2} b)\\\\=\frac{10a+3b}{5} \ . \ \frac{2a-b}{2} \\\\=\frac{(10a+3b)(2a-b)}{5 \ . \ 2} \\\\=\frac{(10a+3b)(2a-b)}{10}$