Question

式子根号（3+根号5）+根号（3-根号5）的化简结果为?

Answer 1

令原式=a

则显然a>=0

a²=3+√5+2√(3+√5)(3-√5)+3-√5

=6+2√(9-5)

=6+2×2

=10

所以原式=√10