Question 184062
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*[tex \LARGE \text{          }\math dy+az]
*[tex \LARGE \text{          }\math ey-bz]


To subtract expressions, change the sign of the subtrahend (the bottom expression) and add:


*[tex \LARGE \text{          }\math dy+az]
*[tex \LARGE \text{          }\math -ey+bz]


*[tex \LARGE \text{          }\math dy - ey + az + bz = (d - e)y + (a + b)z]


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*[tex \LARGE \text{          }\math ax+aby]
*[tex \LARGE \text{          }\math bx+aby]


You don't say, but I presume you want to subtract again, so:


*[tex \LARGE \text{          }\math ax+aby]
*[tex \LARGE \text{          }\math -bx-aby]


*[tex \LARGE \text{          }\math ax - bx + aby - aby = (a - b)x + 0y = (a - b)x]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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