Question

Помогите пожалуйста 1,2,4.срочно надо

Answer 1

$1)quad a); (3sqrt{8} +sqrt{18} +sqrt{50} -2sqrt{72} )cdot sqrt{2} =\\=3sqrt{16}+sqrt{36}+sqrt{100}-2sqrt{144}=3cdot 4+6+10-2cdot 12=4\\b); (3sqrt2+sqrt{50})cdot sqrt2=3sqrt4+sqrt{100}=3cdot 2+10=16\\2)quad frac{1}{x-4} + frac{24}{x^2-16} = frac{x+1}{x+4} ; ,; ; ODZ:; xne pm 4\\ frac{1}{x-4} + frac{24}{(x-4)(x+4)} - frac{x+1}{x+4} =0\\ frac{x+4+24-(x+1)(x-4)}{y} =0;,quad frac{-x^2+4x+32}{(x-4)(x+4)} =0$

 $frac{-(x+4)(x-8)}{(x-4)(x+4)} =0; ,$    $frac{x-8}{x-4} =0$  

$x=8$

$3)\P=2(a+b)=25\\S=ab=34\\ left { {{a+b=12,5} atop {b=frac{34}{a}}} right. left { {{a+frac{34}{a}-12,5=02} atop {b=frac{34}{a}}} right. left { {{frac{a^2-12,5a+34}{a}=0} atop {b=frac{34}{a}}} right. left { {{a_1=4;a_2=8,5} atop {b_1=8,5;b_2=4}} right. \\Otvet:(4;8,5);(8,5;4).$