已知x+1⼀x=3,求(1)x^2+1⼀x^2, (2) (x-1⼀x)^2

2025-01-05 17:04:10
推荐回答(3个)
回答1:

(1)x^2+1/x^2=(x+1/x)^2-2=9-2=7
(2)(x-1/x)^2=x^2+1/x^2-2=7-2=5

回答2:

(1)x^2+1/x^2
=(x+1/x)²-2
=3²-2
=7
(2) (x-1/x)^2
=(x+1/x)²-4
=3²-4
=5

回答3:

(1)x^2+1/x^2=(x+1/x)^2-2=9-2=7
(2) (x-1/x)^2=x^2+1/x^2-2=7-2=5