Question

Desenvolva este produto e reduza os termos semelhantes:

a) ( x+7) ( x-7) - x² + 50

b) (x+1/2)(x-1/2)+3/4

Answer 1

$a) ~~( x+7) ( x-7) - x^2 + 50\to\\\\ (x^2+\not7x-\not7x-49)-x^2+50\to\\\\ \not x^2-49-\not x^2+50\to \\\\ -49+50 = \boxed{1}$




$b)~~ \left(x+ \dfrac{1}{2} \right)\left(x- \dfrac{1}{2} \right)+ \dfrac{3}{4} \to \\\\\\ x^2-\dfrac{1x}{2}+\dfrac{1x}{2}-\dfrac{1}{4}+\dfrac{3}{4}\to\\\\\\x^2-\dfrac{1}{4}+\dfrac{3}{4}\to~~mmc=4\\\\\\ \dfrac{4x^2-1+3}{4} \to\\\\\\ \dfrac{4x^2+2}{4} \to \\\\\\ \boxed{x^2+ \dfrac{1}{2} }$

Answer 2

Resposta:

Explicação passo-a-passo:

a) ( x+7) ( x-7) - x² + 50

= x² - 49 - x² + 50

= 1

b) (x+1/2)(x-1/2)+3/4

= x² - 1/4 + 3/4

= x² + 2/4 (:2)/(:2)

= X² + 1/2