求x^2 (9-x^2)^1 2的积分,令x=3sint

-1=a-1/2-1/6-1/12-1/20'''''''-1/9900-a=1-1/2-1/6-1/12-1/20''''''-1/9900-a=1/100a=-1/100

原式=2X+0.5X=22.5所以2.5X=22.5得出X=22.5/2.5=9再问：谢谢你咯！

x=3/2x(x^3-x)+x^2(5-x)-9=x^4-x^2+5x^2-x^3-9=x^4-x^3+4x^2-9=x^3(x-1)+(2x-3)(2x+3)=x^3(x-1)=(3/2)^3*(1

∵x²+y²-4x+2y+5=0x²-4x+4+y²+2y+1=0(x-2)²+(y+1)²=0x-2=0y+1=0∴x=2y=-14x&#

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

=9x^4+4(x+1)-3x^2-7x+1=9x^4-3x^2-3x+5=9x^4-3x(x+1)+5=9x^4-3x×3x^3+5=5

设x1=4-√3,x2=4+√3,是方程X^2-8X+13=0的两根所以X1^2-8X1+15=2X^4-6X^3-2X^2+18X+23=(X+1)^2*(X^2-8X+13)+10=10所以原式=

(x-2)(x²-6x-9)=x(x²-8x+15)x(x²-6x-9)-2(x²-6x-9)=x(x²-8x+15)x(x²-6x-9)-

是f(x)=2X^3+6x^2-8x,g(x)=9x^5-12x^4+27x^3,求f(x)(-x/2)+g(x)/(3x)发吧?f(x)(-x/2)+g(x)/(3x)=(2X^3+6x^2-8x)

1.求x^21+x^15+x^12+x^9+x^6+x^3+1被x^2+x+1除所得的余式答：原式=[x^21+x^18-x^18-x^15+2*x^15+2*x^12-x^12-x^9+2*x^9+

[(x^2)^2-2x^2*x+x^2]-(2x^2+2x+1)=0即(x^2-x)^2-(2x^2-2x)-4x+1=0[(x(x-1))^2-2(x(x-1))+1]-4x=0(x(x-1)-1)

f(x)=(x-2)^2/(x+1)f(x)'=[2(x-2)(x+1)-1*(x-2)^2]/(x+1)^2=(x-2)(x+4)/(x+1)^2f(x)=(x^2+9)(x-3/x)f(x)'=(

等价于(2x-3)^2=0得x=1.5

1.f(x)求导得f'(x)=6x²-18x+12,当f'(x)≥0时f(x)单调递增,X的取值范围即为递增区间当f'(x)≤0时f(x)单调递减,X的取值范围即为递减区间2.y求导得y'=

2x-3=0∴x=3/2x(x²-x)+x²(5-x)-9=x²(x-1)+x²(5-x)-9=4x²-9当x=3/2时上式=4×（3/2）²

1.5!

因为|x|=x+2所以x=x+2或-x=x+2x=-12x³+3x²+9=2×(-1)³+3×(-1)²+9=-2+3+9=10

每两项合并,即(1+x)+(1+x)*x^2+(1+x)*x^4+(1+x)*x^6+(1+x)*x^8=0提取公因式(1+x),得到(1+x)(1+x^2+x^4+x^6+x^8)=0等式左边的两个

原式=X²-9=-6再问：这两个&#是？再答：你发的什么乱码原式=X平方-9=-6

x/2+x/8+x/12+x/20+x/30+x/42=x/2+x/8+(x/3-x/4)+(x/4-x/5)+(x/5-x/6)+(x/6-x/7)=x/2+x/8+x/3-x/7=137x/168