若X≠0,当a为何值时,多项式(2ax方—x方+3x+2)—(5x方—4x方+3x)的值恒为2?

问题描述:

若X≠0,当a为何值时,多项式(2ax方—x方+3x+2)—(5x方—4x方+3x)的值恒为2?

(2ax²-x²+3x+2)-(5x²-4x²+3x)
=2ax²-x²+3x+2-5x²+4x²-3x
=(2a-2)x²+2
当2a-2=0,即a=1时,多项式(2ax方—x方+3x+2)—(5x方—4x方+3x)的值恒为2

(2ax方—x方+3x+2)—(5x方—4x方+3x)
=2ax²-5x²-x²+4x²+3x-3x+2
2a+4=5+1
a=1
当a为1时,多项式(2ax方—x方+3x+2)—(5x方—4x方+3x)的值恒为2.