ppts.net
当前位置:首页>>关于(1) 3x^3-2x-1 (2)x^3+6x^2+11x+6 (3)x^4+2x^3-9x^...的资料>>

(1) 3x^3-2x-1 (2)x^3+6x^2+11x+6 (3)x^4+2x^3-9x^...

(1) 3x^3-2x-1=(3x+1)(x-1) (2)x^3+6x^2+11x+6 =x^3+2x^2+4x^2+8x+3x+6 =x^2(x+2)+4x(x+2)+3(x+2) =(x+2)(x^2+4x+3) =(x+2)(x+1)(x+3) (3)x^4+2x^3-9x^2-2x+8 = x^4-2x^3+4x^3-8x^2-x^2+2x-4x+8 =x^3(x-2)+4x^2(x-2)-x(x-2)-4(x-2) =(x-2)(x^3+4...

将分子分母同时除以 x^5, 得到原极限 =lim(x→∞) [(2-1/x)^2 * (3+2/x)^3] /(6+1/x)^5 那么在x趋于无穷大的时候, 1/x和2/x都是趋于0的, 于是就得到 原极限= 2^2*3^3 /6^5 =1/72

x1+x2+2X3+3X4=1 X1+3X2+6X3+X4=3 X1-5X2-10X3+9X4=a 增广矩阵= 1 1 2 3 1 1 3 6 1 3 1 -5 -10 9 a r2-r1,r3-r1 1 1 2 3 1 0 2 4 -2 2 0 -6 -12 6 a-1 r3+3r2,r2*(1/2),r1-r2 1 0 0 4 0 0 1 2 -1 1 0 0 0 0 a+5 所以 a=-5 时方程组有解 通解为 (...

(3x+5)^2(3x+7)(x+1)-4 =(9x^2+30x+15)(3x^2+10x+7)-4 =3(3x^2+10x+5)^2+6(3x^2+10x+5)-4,① 设y=3x^2+10x+5,则 ①=3y^2+6y-4=3[y-(-3+√21)/3][y-(-3-√21)/3] =3[3x^2+10x+5-(-3+√21)/3][3x^2+10x+5-(-3-√21)/3] =[9x^2+30x+18-√21][3x^2+10x+5-(-...

(1)原式=2(x+3)+2x?18?x?32(x+3)(x?3)=3x?152x2?18;(2)原式=x2+2x+4(x+2)2?3(x+2)2(x+2)(x?2)?(x+2)(x-2)=3x2+6x+122x+4.

解:原式=x³+5x²+4x-3+x²-2x³+3x+1+4-7x- 6x²+x³ =(1-2+1)x³+(5+1-6)x²+(4+3-7)x- 3+1+4 =0x³+0x²+0x-(3-1-4) =2

高三月考吧 2/(x-1)>1,即(x-3)/(x-1)<0 得x∈(1,3) 2x³+3x²≥6(6x+a) 即6a≤2x³+3x²-36x 令f(x)=2x³+3x²-36x,求导得f’(x)=6x²+6x-36 f’(x)=0得x1=-3,x2=2,于是可判断f(x)在(-3,2)为减...

(1)3a^4-8a^2-16 =(3a²+4)(a²-4) =(3a²+4)(a+2)(a-2) (2)2x^3-x^2-15x =x(2x²-x-15) =x(2x+5)(x-3) (3)3x^2-10x-8 =(3x+2)(x-4) (4)2x^2+x-15 =(2x-5)(x+3) (5)6x^2-11x+3 =(2x-3)(3x-1) (6)4x^2+5x-6 =(4x-3)(x+2) (7)...

lim( x³-3x +2)/(x^4-4x +3)=lim(x-1)²(x+2)/[(x-1)²(x²+2x+3)]=lim(x+2)/(x²+2x+3) x→1 =3/6=1/2 因为:x³-3x+2=x³-1-3x+3=(x²+x+1)(x-1)-3(x-1)=(x-1)(x²+x-2)=(x-1)²(x+2) x^4-4x+3=x^4-1...

网站首页 | 网站地图
All rights reserved Powered by www.ppts.net
copyright ©right 2010-2021。
内容来自网络,如有侵犯请联系客服。zhit325@qq.com