Question

二次根式计算题100道带答案

Answer 1

①5√8-2√32+√50 =5*3√2-2*4√2+5√2 =√2(15-8+5) =12√2 ②√6-√3/2-√2/3 =√6-√6/2-√6/3 =√6/6 ③(√45+√27)-(√4/3+√125) =(3√5+3√3)-(2√3/3+5√5) =-2√5+7√5/3 ④(√4a-√50b)-2(√b/2+√9a) =(2√a-5√2b)-2(√2b/2+3√a) =-4√a-6√2b ⑤√4x*(√3x/2-√x/6) =2√x(√6x/2-√6x/6) =2√x*(√6x/3) =2/3*|x|*√6 ⑥(x√y-y√x)÷√xy =x√y÷√xy-y√x÷√xy =√x-√y ⑦(3√7+2√3)(2√3-3√7) =(2√3)^2-(3√7)^2 =12-63 =-51 ⑧(√32-3√3)(4√2+√27) =(4√2-3√3)(4√2+3√3) =(4√2)^2-(3√3)^2 =32-27 =5 ⑨(3√6-√4)2 =(3√6)^2-2*3√6*√4+(√4)^2 =54-12√6+4 =58-12√6 ⑩（1+√2-√3）（1-√2+√3） =[1+(√2-√3)][1-(√2-√3)] =1-(√2-√3)^2 =1-(2+3+2√6) =-4-2√6