Question

Помогите решить 3,5 и 6 номер пожалуйста

Answer 1

$3)4x^{2}+bx+3=0|:4\\\\x^{2} +0,25b+0,75=0\\\\x_{1} =3\\\\x_{1} *x_{2}=0,75\\\\x_{2}=0,75:x_{1} =0,75:3=0,25\\\\x_{1} +x_{2}=-0,25b\\\\-0,25b=3+0,25\\\\-0,25b=3,25\\\\b=-13\\\\\boxed{x_{2}=0,25 \ ; \ b=-13}$

$5)4x^{2}-8x+p=0\\\\D=(-8)^{2}-4*4*p=64-16p\\\\D=0 \ \Rightarrow \ 64-16p=0\\\\16p=64\\\\\boxed{p=4}\\\\\\6)x^{2}+10x+5=0\\\\x_{1} +x_{2}=-10\\\\x_{1} *x_{2}=5\\\\x_{1} ^{2}+x_{2}^{2} =(x_{1} +x_{2})^{2}-2x_{1}*x_{2}=(-10)^{2}-2*5=100-10=90\\\\\boxed{x_{1} ^{2}+x_{2}^{2} =90}$