Question

urgente preciso dessa duas resposta

Answer 1

b) (y+2).(y-2)-(y+3).(y-3)=
     (y² - 2²) - (y² - 3²) =
     y² - 4 - y² + 9 = -4 + 9 = 5

c)$( \frac{1}{2} -m)( \frac{1}{2} +m)-( \frac{1}{2}-m)^2= ( \frac{1}{2})^2-(m^2)-[( \frac{1}{2} )^2-2. \frac{1}{2}.m+m^2]=$

$\frac{1}{4} -m^2-[ \frac{1}{4} -m+m^2]= \frac{1}{4} -m^2- \frac{1}{4} +m-m^2=$

$-2m^2+m=-m(2m-1)$