- 问一个数学问题36X
- 36X-6Y-26=6√37c(a+b)+46 X=2+cosa Y=sina
怎么从36X-6Y-26到6√37cos(a+b)+46 ?
- 36X-6Y-26=6√37cos(a+b)+46 X=2+cosa Y=sina
怎么从36X-6Y-26到6√37cos(a+b)+46 ?
已知:X=2+cosa Y=sina
所以:36X-6Y-26=36*(2+cosa)-6sina-26=72+36cosa-6sina-26
=36cosa-6sina+46
=√[36^2+6^2]*{(36/√[36^2+6^2])*cosa-(6/√[36^2+6^2])*sina}+46
=6√37*[(6/√37)cosa-(1/√37)sina]+46
=6√37cos(a+b)+46
其中:tanb=(1/√37)/(6/√37)=1/6