绝大多数非线性微分方程是不能用解析方法求解的.The overwhelming majority of nonlinear differential equations are not soluble analytically.与微分相反的运算叫做积分.The operation that is the inverse of differentiation is called integration.这称为正规微分方程组.This is...
劳拉松开离合器踏板,沿车道慢慢驶离。Laura let out the clutch and pulled slowly away down the drive.踏板似乎有点偏心,离合器也相当紧。The pedals seem a bit off-centre and the clutch is rather stiff.离合器失灵后,汽车只能在二挡行驶。When the clutch broke, the car was locked...