vb求和,求sin(x)=x/1-x^3/3!+x^5/5!- …… (-1)^(n-1)* x^(2*n-1)/(2n

Private Sub Form_Click()
Dim x%,s!,i%,q%
x = Val(InputBox("请输入X的值"))
Do While t >= 10 ^ (-5) '问题出在这里,因为t的初值是0,所以t
再问： 不对，我试了下，可以再帮我看看嘛，新手学VB，灰常感谢
再答： 其实我是学Pascal的，但是在学校的计算机课上学了些VB。 我编的程序如下，因为比如说5！=3！*4*5，x^5=x^3*x^2，所以可以把程序化简一下： Private Sub Form_Click() Dim i As Long, n As Long, t As Double, s As Double x = Val(InputBox("Input x")) t = x s = 0 n = 1 Do While Abs(t) >= 10 ^ (-5) s = s + t t = t / ((n + 1) * (n + 2)) * (-1) * x ^ 2 n = n + 2 Loop Print "s="; s End Sub 如果要用你以前的方法，那么就像下面： Private Sub Form_Click() Dim x As Long, k As Long, n As Long, s As Double, q As Double, t As Double x = Val(InputBox("请输入X的值")) Do While True q = 1 For k = 1 To 2 * n - 1 q = q * k Next k t = ((-1) ^ (n - 1)) * (x ^ (2 * n - 1)) / q If Abs(t) < 10 ^ (-5) Then Exit Do s = s + t n = n + 1 Loop Print "s="; s End Sub 数据定义的时候可以阔气一点，多用一些Long、Double，少用一些Integer和Real，但是也要依情况而定。