解由A+B=3x²-5x+1......................(1)
A-C=-2x+3x²-5,...........................(2)
由(1)-(2)得
B+C=-3x+6
故当x=2时,B+C=-3x+6=-3×2+6=0.
解由A+B=3x²-5x+1......................(1)
A-C=-2x+3x²-5,...........................(2)
由(1)-(2)得
B+C=-3x+6
故当x=2时,B+C=-3x+6=-3×2+6=0.