Question

若a的平方减3a加1等于零,则3倍a的平方减8倍a的平方加a加a的平方加1分子3的值为?

Answer 1

由原式可得a*a=3a-1,a*a+1=3a

原式=3a(3a-1)-8a*a++a+3/3a

=9a*a-3a-8a*a+a+1/a

=a*a-2a+1/a

=3a-1-2a+1/a

=a+1/a-1

=(a*a+1)/a-1

=3a/a-1

=2

好啦,得解