4/5x2=4x2一5x2=8/10=4/5是对还是错

4x2.5x2+4x2×2+2x2.5x2= 4/5x2=4x2一5x2=8/10=4/5是对还是错 5X2+4=? mathematica如何求解含有三角函数的方程?FindRoot[{3 x1^3 + 2 x2 - 5 + Sin[x1 - x2] Sin[x1 + x2] == 0,-x1*Exp[x1 - x2] + x2 (4 + 3 x2^2) + 2 x3 + Sin[x2 - x3] Sin[x2 + x3] - 8 == 0,-x2*Exp[x2 - x3] + 4 x3 - 3 ==0},{x1,Pi/2},{x2,2},{x3,0}] √(x2-25/4)+√(x2-9/4)=5 求值域:y=(x2+5)/根号(x2+4) 求y=x2+5/根号x2+4的最小值 2/5x2/4=? 不等式(x2-4x-5)(x2-8) 解分式方程:2/x2+5x+6 + 3/x2+x-6=4/x2-4 已知x2-5x+=0,求x2-4x2-1 1/(x2+x)+1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=4/21x2是x的平方 用excel解 （1）maxz=2x1+2x2 (2)maxz=X1+X2 (3)maxz=10x1+5x2 (4)maxz=2x1+x2 （5）maxz=3x1+5x2（1）maxz=2x1+2x2 x1-x2>=-1-0.5x1+x2=0(2)maxz=X1+X2 x1-x2>=03x1-x2=0(3)maxz=10x1+5x23x1+4x2 因式分解 x2-4=? 因式分解;x2-4= max Z=2X1+4X2-5X3 X1+X2+X3=7 2X1-3X2+X3≥10 X1.X2.X3≥0 2^5+5x2^4+10x2^3+10x2^2+5x2+1 已知x2－4x+1=0,求x2／(x2)2－3x2+1