trig/calc question

[Raven]

It's been a while since I took trig and calc.
I know that...
sin(x) dx = cos(x)
cos(x) dx = -sin(x)

but, remind me...
-sin(x) dx = ?? -cos(x) ?
-cos(x) dx = ?? sin(x) ?

Thanks

[Katon]

-sin(x)dx=-(sin(x) dx)=-cos(x). Multiplying by constants - such as -1 - doesn't change a differential equation.

[Craptacular]

I think your original assumption is wrong. Isn't cos the derivative of sin, not the antiderivative? It should be d/dx sin(x) = cos(x)

[Raven]

That's what I was saying. Though maybe my syntax was wrong.

the derivative of sin(x) is cos(x) is what I was trying to write.

[terpkristin]

The way I always remembered it was:
S
C
-S
-C

For the derivative, you move down, for the integral, you move up.
I.e. d/dx sin(x) = cos(x)
d/dx cos(x) = -sin(x)
d/dx -sin(x) = -cos(x)

This is what Katon said, I just wanted to give you a memory aid.

/tk

[PackerFanatic]

Wow, and I had almost forgot why I hated trig and calc...now I remember...

*head hurts*

[finkenst]

Wow, and I had almost forgot why I hated trig and calc...now I remember...

*head hurts*

here here