25.计算星形线 =a(cos )^3t, =a(sin )^3t 图 -26 的全长.
18.[多选题] 设星形线{}x=acos^3t,y=asin^3t.t)dt.A. 它所围图形的面积为$A=4\int_{\frac{\pi}{6}}^{\f
6.求由下列各曲线所围成的图形的面积:(1)ρ=2acosθ; (2)x=acos^3t,y=asin^3t; (3)ρ=2a(2+cosθ).6.求由下列
2.应用格林公式计算下列曲线所围的平面面积:-|||-(1)星形线: =a(cos )^3t, =a(sin )^3t;-|||-(2)双纽线: (({x)^2
1.求下列曲线的弧长:-|||-(1) =(x)^3/2, (2)、 sqrt (x)+sqrt (y)=1;-|||-(3) =a(cos )^3t, =a(
6.求由下列参量方程所确定的函数的二阶导数 dfrac ({d)^2y}(d{x)^2}:-|||-(1) ) x=a(cos )^3t, y=a(sin
[题目]-|||-4.求曲线 =a(cos )^3t =a(sin )^3t 在 =(t)_(0) 相应的点处的曲率.
求振动_(1)=4cos 3t和_(1)=4cos 3t (SI)的合振动方程.求振动和(SI)的合振动方程.
2.求下列各曲线在指定点处的曲率:-|||-(4) =a(cos )^3t, =a(sin )^3t(agt 0), 在 =dfrac (pi )(4) 的点.