已知X的平方减5X 减14 等于0,求X减1的差乘2X减1的差减去X加1的和的平方加1

x²-5x-14=0
x²-5x=14
(x-1)(2x-1)-(x+1)²
=2x²-x-2x+1-x²-2x-1
=2x²-3x+1-x²-2x-1
=x²-5x
=14