Question

(3-√2)*(5+√8) упростите выражение напишите как положено плз

Answer 1

$(3-sqrt{2})*(5+sqrt{8})=3*5+3*sqrt{8}-sqrt{2}*5-sqrt{2}*sqrt{8}=\\15+3*sqrt{4*2}-5sqrt{2}-sqrt{2*8}=\\15+3sqrt{2}*sqrt{4}-5sqrt{2}-sqrt{16}=\\15+3*2sqrt{2}-5sqrt{2}-4=\\11+6sqrt{2}-5sqrt{2}=11+sqrt{2}$