Question

помогите
(x2-1)(x2-8x+7)=>0

Answer 1

$(x^2-1)(x^2-8x+7) geq 0\\(x-1)(x+1)(x-1)(x-7) geq 0\\(x-1)^2(x+1)(x-7) geq 0\\+++(-1)---(1)---(7)+++\\xin (-infty,-1, ]U[, 7,+infty)$