计算(7+2√5)(7-2√5)-5√18+8√8
问题描述:
计算(7+2√5)(7-2√5)-5√18+8√8
答
(7+2√5)(7-2√5)-5√18+8√8
=7²-(2√5)²-5×3√2+8×2√2
=49-20-15√2+16√2
=29+√2