1.2x4.3+9.8x5.7如何简算?

1.2x4.3+9.8x5.7如何简算? 3.4X5.3+5.9X4.7+2.5X5.3 8.6x5.7+4.3x4.3x2 巧算就 巧 算 无补充 8.6X5.7+4.3X4.3X2该怎样巧算?巧算? 8.6x5.7+4.3x4.3x2（巧算） 解方程组:x1+x2+x3+x4+x5=7 3x1+2x2+x3+x4-3x5=－2 x2+2x3+2x4+6x5=23 5x1+4x2-3x3+3x4-x5=10 X1 - X3 - X4 -5X5=0 X1+2X2+3X3+3X4+7X5=0 X1+X2+X3+X4+X5=0 X2+2X3+2X4+6X5=0 关于二元一次方程组若X1,X2,X3,X4,X5满足下列方程组:2X1+X2+X3+X4+X5=6X1+2X2+X3+X4+X5=12X1+X2+2X3+X4+X5=24X1+X2+X3+2X4+X5=48X1+X2+X3+X4+2X5=96则3X4+2X5的值是 多少?(X1,X2.X3.X4.X5的1.2.3.4.5不是乘除和加减,带表5个不同的 解线性方程组 X1-X2+2X4+X5=0 3X1-3X2+7X4=0 X1-X2+2X3+3X4+2X5=0 2X1-2X2+2X3+7X4-3X5=0 解线性方程组 X1-X2+2X4+X5=0 3X1-3X2+7X4=0 X1-X2+2X3+3X4+2X5=0 2X1-2X2+2X3+7X4-3X5=0 2.2x3.3+3.3x4.4+4.4x5.5 如何简便计算 求解奇次线性方程组{上面2x1+x2+3x3+5x4-5x5 =0 中x1+x2+x3+4x4-3x5=0 下面3x1+x2+5x3+6x4-7x5=0 求方程组x1+3x2+x3+2x4+4x5=3 2x1-x2+8x3+7x4+2x5=9 4x1+5x2+6x3+11x4+10x5=15的全部解线性代数 x1 + x2 + x3 + x4 + x5 = 7 4x1 + 2x2 + 3x3 + 2x4 - 2x5 = 5 x1 + 3x2 + 2x3 + 3x4 + 7x5 = 30求这方程组的通解 并指出它的一个特解x1 + x2 + x3 + x4 + x5 = 7 4x1 + 2x2 + 3x3 + 2x4 - 2x5 = 5 x1 + 3x2 + 2x3 + 3x4 + 7x5 = 30 matlab线性方程组计算X1+X2-5X3-X4+X5=98X1+5X2-X3+4X5=23X1-7X2-5X3-X4+X5=42X1+X2+8X3+3X4-X5=-86X2+2X3+7X4-2X5=15 sinx+sin(paix)的周期（x1+x2+x3+x4+x5)^7被展开时x1^2*x3*x4^3*x5的系数sinx^3cosx^4的最大值 化简：(1x3)分之一+(2x4)分之一+(3x5)分之一+...+(7x9)分之一+(8x10)分之一 求非齐次线性方程组通解X1+X2+X3+3X4+X5=7 3X1+X2+2X3+X4-3X5=-2 2X2+X3+2X4+6X5=23 8X1+3X2+4X3+3X4-X5=12