分解因式(x'2十x一6)(x'2十x一8)一24;(x十1)(x一2)(x一3)(x一6)十20;
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分解因式(x'2十x一6)(x'2十x一8)一24;(x十1)(x一2)(x一3)(x一6)十20;
分解因式(x'2十x一6)(x'2十x一8)一24;(x十1)(x一2)(x一3)(x一6)十20;
分解因式(x'2十x一6)(x'2十x一8)一24;(x十1)(x一2)(x一3)(x一6)十20;
(x²+x-6)(x²+x-8)-24
=(x²+x-6)[(x²+x-6)-2]-24
=(x²+x-6)²-2(x²+x-6)-24
=[(x²+x-6)-6][(x²+x-6)+4]
=(x²+x-12)(x²+x-2)
=(x-3)(x+4)(x-1)(x+2)
(x+1)(x-2)(x-3)(x-6)+20
=[(x+1)(x-6)][(x-2)(x-3)]+20
=(x²-5x-6)(x²-5x+6)+20
=(x²-5x)²-36+20
=(x²-5x)²-16
=(x²-5x+4)(x²-5x-4)
=(x-1)(x-4)(x²-5x-4) (有理数范围内到此为止)
=(x-1)(x-4)[x-(5+√41)/2][x-(5-√41)/2] (实数范围内)
(1)x'2十x一6=(x+3)(x-2)
(2 )(x'2十x一8)一24=x²+x-32=(x+ 1/2)²- 129/4
=(x+1/2 - (根号129)/2)(x+1/2+ (根号129)/2)
(3);(x十1)(x一2)(x一...
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(1)x'2十x一6=(x+3)(x-2)
(2 )(x'2十x一8)一24=x²+x-32=(x+ 1/2)²- 129/4
=(x+1/2 - (根号129)/2)(x+1/2+ (根号129)/2)
(3);(x十1)(x一2)(x一3)(x一6)十20
=(x²-5x-6)(x²-5x+6)+20
=(x²-5x)²-36+20
=(x²-5x)²-16
=(x²-5x+4)(x²-5x-4)
=(x-1)(x-4)[(x-5/2)²-41/4]
=(x-1)(x-4)(x-5/2- (根号41)/2)(x-5/2 + (根号41)/2)
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