Question 1184646


{{{sqrt(7)(sqrt(21)+sqrt(7)) }}}

={{{sqrt(7)(sqrt(3*7))+sqrt(7))}}}

={{{sqrt(7)(sqrt(3)sqrt(7)+sqrt(7))}}}

={{{sqrt(7)sqrt(7)(sqrt(3)+1)}}}

={{{(sqrt(7))^2(sqrt(3)+1)}}}

={{{7(sqrt(3)+1)}}}

={{{7sqrt(3)+7}}}