Question

ПОМОГИТЕ С ПЕРВЫМ!!!СРОЧНО

Answer 1

$1); ; f(x)=sqrt{x+2}+frac{x-7}{x^2-4}\\OOF:; ; left { {{x+2geq 0} atop {x^2-4ne 0}} right. ; ; left { {{xgeq -2} atop {xne -2; ,; xne 2}} right. ; Rightarrow ; ; xin (-2,2)cup (2,+infty )\\2); ; f(x)=sqrt{x-9}+frac{6}{sqrt{8-x}}\\OOF:; ; left { {{x-9geq 0} atop {8-x>0}} right. ; left { {{xgeq 9} atop {x<8}} right. ; ; Rightarrow ; ; xin varnothing$

$3); ; f(x)=frac{sqrt{x-6}}{sqrt{x+3}}+frac{5x-4}{x^2-8x+7}\\OOF:; ; left { {{x-6geq 0; ,; x+3>0} atop {x^2-8x+7ne 0}} right. ; left { {{xgeq 6; ,; x>-3} atop {xne 1; ,; xne 7}} right. ; Rightarrow ; xin [, 6,7)cup (7,+infty )$