Question

помогите решить, пожалуйста

Answer 1

$sqrt{x-3} leq x+5quad Leftrightarrow ; ; ; left { {{x+5 geq 0; ,; x-3 geq 0} atop {x-3 leq (x+5)^2}} right. ; left { {{x geq 3} atop {x-3 leq x^2+10x+25}} right. \\ left { {{x geq 3} atop {x^2+9x+28 geq 0}} right. \\x^2+9x+28=0\\D=81-4cdot 28=81-112=-31 textless 0; ; Rightarrow \\ x^2+9x+28 textgreater 0; ; pri; ; xin (-infty ,+infty )\\ left { {{xin [, 3,+infty )} atop {xin (-infty ,+infty )}} right. ; ; Rightarrow ; ; ; xin [, 3,+infty )$