Question

a+a的负1次方=3那么a的2/1次方-a-2/1 和a的3/2-a-3/2的值是多少?

Answer 1

[a^(1/2)-a^(-1/2)]^2=a+a^(-1)-2=3-2=1

a^(1/2)-a^(-1/2)=±1

a^(3/2)-a^(-3/2)=[a^(1/2)-a^(-1/2)][a+1+a^(-1)]

=(±1)(3+1)

=±4