So, when you go to polar coordinates, basically all you have to remember on the side of integrate is that x becomes r cosine theta. y becomes r sine theta.

在极坐标系里，要记住在积分一侧,只是把x变成rcosθ，y变成rsinθ

youdao

But, basically you don't really need to remember these formulas as long as you remember how to express r in terms of rho sine phi, and x equals r cos theta.

事实上你不用记住这些公式,只需要知道r=ρ*sinφ,而x=r*cosθ

youdao

But, basically you don't really need to remember these formulas as long as you remember how to express r in terms of rho sine phi, and x equals r cos theta.

事实上你不用记住这些公式,只需要知道r=ρ*sinφ,而x=r*cosθ

youdao