Question

Помогите пожалуйста!!!Срочно!!!

Answer 1

$2x^{2}-5x-4=0\\\\x_{1}+x_{2}=\frac{5}{2} =2,5\\\\x_{1} *x_{2}=\frac{-4}{2}=-2\\\\x_{1}^{2} +x_{2}^{2} =(x_{1}+x_{2})^{2} -2x_{1}x_{2}\\\\\frac{1}{x_{1 }^{2}}+\frac{1}{x_{2} ^{2}}=\frac{x_{1}^{2} +x_{2} ^{2}}{x_{1}^{2} x_{2}^{2}}=\frac{2,5^{2}-2*(-2) }{(-2)^{2} }=\frac{6,25+4}{4}=\frac{10,25}{4}=2,5625$

2) x₁x₂⁴ + x₂x₁⁴ = x₁x₂(x₁³ + x₂³) = x₁x₂(x₁ + x₂)((x₁ + x₂)² - 3x₁x₂) =

= - 2*2,5*(2,5² - 3*(-2)) = -2*2,5*(6,25+ 6) = -5 * 12,25 = - 61,25