Question

Calcule:

A) 2ab × 6ac

B) -8a^2 ÷ 4a

C) (a - 7) × (a - 9)

D (-2x^3 + 4x^2 - 10x) ÷ (2x)

Answer 1

Resposta:

Explicação passo-a-passo:

$\displaystyle a)~2ab.6ac=2.6.a^{(1+1)}.b.c=12a^2bc\\\\b)~-8a^2\div4a=-\frac{8a^2}{4a} =-\frac{8}{4}.\frac{a^2}{a} =-2.a^{(2-1)}=-2a^1=-2a\\\\c)~(a-7)(a-9)=a.a-9a-7a+63=a^{(1+1)}-16a+63=a^2-16a+63\\\\d)~(-2x^3+4x^2-10x)\div(2x)=\frac{-2x^3+4x^2-10x}{2x} =-\frac{2x^3}{2x} +\frac{4x^2}{2x} -\frac{10x}{2x} =-x^{(3-1)}+2x^{(2-1)}-5x^{(1-1)}=-x^2+2x^1-5x^0=-x^2+2x-5$