Question

数学二次根式题目？较难

Answer 1

a+b

=（根号a+根号b)^2-2*根号ab

=(根号3+根号2)^2-2*(根号6-根号3)

=3+2+2根号6-2根号6-2根号3

=5-2根号3

Answer 2

(√a + √b)^2 = a +2√(ab) + b = (√3 + √2)^2 = 3 + 2 + 2√6
√(ab) = √6 - √3
=> a+b = 5 + 2√6 - 2√(ab)
= 5 + 2√6 - 2 (√6 - √3)
= 5 + 2√3

Answer 3

其实这道题很简单啊~~~~~~

Answer 4

所以：(√a + √b)^2 = a +2√(ab) + b = (√3 + √2)^2 = 3 + 2 + 2√6
√(ab) = √6 - √3
=> a+b = 5 + 2√6 - 2√(ab)
= 5 + 2√6 - 2 (√6 - √3)
= 5 + 2√3