Question

(y-3)(y+3)-(2+y)^2 при y=-2,5
упростите и найтите значение

Answer 1

y^2 - 9 - (y^2 + 4y + 4) = y^2 - 9 - y^2 - 4y - 4 = - 4y - 13

y = - 2,5

- 4*(-2,5) - 13 = 10 - 13 = - 3