By use of the common formula for solving the time variations of the crustal density, the approximative planeformula is derived and its numerical calculation method is given.
采用求解地壳单层密度变化的一般公式，导出其平面近似公式并给出了相应的数值计算方法。
2
Well, we've seen a formula, for example, for a horizontal plane, or for something that's parallel to the yz plane or the xz plane.
我们已经学过一个公式，它是关于水平面的，或者某些平行于yz平面或xz平面的平面。
3
And, the formula for curl in the plane was kind of complicated.