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先化简,再求值:(x+1)(2x%1)%(x%3)²,...

原式=x?1?x+3x+1?(x+1)22=2x+1?(x+1)22=x+1,当x=3-1时,原式=3-1+1=3.

(2x-1)²+(x+2)(x-2)-4x(x-1) =4x²+1-4x+x²-4-4x²+4x =x²-3 =3²-3 =6

由2x/(x+1)-(2x+6)/(x²-1)÷(x+3)/(x²-2x+1) =2x/(x+1)-2(x+3)/(x+1)(x-1)×(x-1)²/(x+3) =2x/(x+1)-2(x-1)/(x+1) =1/(x+1) =1/(√2-1+1) =√2/2.

(1)原式=x 2 -x+2x 2 +2x-6x 2 +17x-5=(x 2 +2x 2 -6x 2 )+(-x+2x+17x)-5=-3x 2 +18x-5当x=2时,原式=19(2)原式=-m 2 ?m 4 ?(-m 3 )=m 2 ?m 4 ?m 3 =m 9 当m=-2时,则原式=(-2) 9 =-512

x²-x-1=0 x²-x=1 x²-x+1/4=1+1/4 (x-1/2)²=5/4 x-1/2=±√5/2 x=1/2±√5/2=(1±√5)/2 x²=(1±2√5+5)/2=(6±2√5)/2=3±√5 x³=(1±3√5+15±5√5)/8=(16±8√5)/8=2±√5 (1-3/x+2)÷x-1/x²+2x-x/x+1 =(3-3/x)÷x-1/x²+2...

[1/(x+1)+(x^2-2x+1)(x^2-1)]/[(x-1)/(x+1)] =[1/(x+1)+(x-1)^2/(x-1)(x+1)]/[(x-1)/(x+1)] =[1/(x+1)+(x-1)/(x+1)]*(x+1)/(x-1) =1/(x+1)*(x+1)/(x-1)+(x-1)/(x+1)*(x+1)/(x-1) =1/(x-1)+1 =(1+x-1)/(x-1) =x/(x-1) =3/(3-1) =3/2

(1)4(x+1)2-2x(2x-3)=4x2+8x+4-4x2+6x=14x+4,当x=-3时,原式=14×(-3)+4=-38;(2)(x+2)(x-2)-(x+3)(x-1)=x2-4-x2-2x+3=-2x-1,当x=2时,原式=-2×2-1=-5.

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