Question

сократите дробь :
а)
7+√7/√56+√8
б)
400-8/20+√8

Answer 1

$frac{7+sqrt{7}}{sqrt{56}+sqrt{8}}=frac{sqrt{7}(sqrt{7}+1)}{sqrt{8}(sqrt{7}+1)}=frac{sqrt{7}}{sqrt{8}}=frac{sqrt{7}}{2sqrt{2}}=frac{1}{2}sqrt{3,5}\\frac{400-8}{20+sqrt{8}}=frac{(20-sqrt{8})(20+sqrt{8})}{20+sqrt{8}}=20-sqrt{8}$