已知ab=6,且1/(a²)+1/(b²)=5,试求(a-b)²的值急需!谢谢!给你们加分!

已知ab=6,且1/(a²)+1/(b²)=5,试求(a-b)²的值急需!谢谢!给你们加分!
已知ab=6,且1/(a²)+1/(b²)=5,试求(a-b)²的值
急需!谢谢!给你们加分!

已知ab=6,且1/(a²)+1/(b²)=5,试求(a-b)²的值急需!谢谢!给你们加分!
1/(a²)+1/(b²)=5
a^2+b^2=5a^2b^2=5(ab)^2=180
(a-b)^2
=a^2+b^2-2ab
=180-12
=168