Question

5,6,7,8 нужен ответы

Answer 1

$5)(3 frac{2}{3})^2- (2frac{1}{3})^2=(3 frac{2}{3}-2 frac{1}{3})(3 frac{2}{3}+2 frac{1}{3})=1 frac{1}{3}*6= frac{4*6}{3}= frac{24}{3}=8;$
$6)(4 frac{1}{6})^2-(1 frac{1}{6})^2=(4 frac{1}{6}-1 frac{1}{6})( 4frac{1}{6}+1 frac{1}{6})=3*5 frac{1}{3}= frac{3*16}{3}=16;$
$7)(5 frac{2}{3})^2-(4 frac{1}{3})^2=(5 frac{2}{3}-4 frac{1}{3})(5 frac{2}{3}+4 frac{1}{3})=1 frac{1}{3}*10= frac{4*10}{3}= frac{40}{3}=13 frac{1}{3};$
$8)21,3^2-21,2^2=(21,3-21,2)(21,3+21,2)=0,1*42,5=4,25;$
Применял формулу: $a^2-b^2=(a-b)(a+b);$