Thread: derivative

can anyone plz help me find the derivtives to these equations??
cos3x/(2+sinx)

lnx/(x((lnx)^4)-1) x>0

dx/(2+sinx+2cosx)

sqr((x-3)/(x+3)

Originally Posted by crazyhanna

can anyone plz help me find the derivtives to these equations??
cos3x/(2+sinx)

lnx/(x((lnx)^4)-1) x>0

dx/(2+sinx+2cosx)

sqr((x-3)/(x+3)

Hold on and I will post the solutions; can you try to make #2 a bit neater. Is the x*ln(x)^4-1?

Originally Posted by crazyhanna

can anyone plz help me find the derivtives to these equations??
cos3x/(2+sinx)

Use the quotient and chain rules together:
y = cos(3x)/(2+sin(x))

y' = [-sin(3x)*3 * (2 + sin(x)) - cos(3x) * (cos(x))]/[2 + sin(x)]^2

y' = -[3sin(3x)*(2 + sin(x)) + cos(x)*cos(3x)]/[2 + sin(x)]^2

-Dan

Originally Posted by crazyhanna

sqr((x-3)/(x+3)

Here it is...

It shouldn't be dy/dx ?

Regards.

RE: Good Point!!

Originally Posted by crazyhanna

can anyone plz help me find the derivtives to these equations??
cos3x/(2+sinx)

lnx/(x((lnx)^4)-1) x>0

dx/(2+sinx+2cosx)

sqr((x-3)/(x+3)

RE: