Solving Trig Problem: solve sin(6x) = cos(9x)

[mike10210]

My math teacher gave this problem on my homework, and i have no idea how to do it. :?:

sin(6x)=cos(9x)

do you have to use the double angle formula? but that is sin(2a)=2sin(a)cos(a) so it still has two variables.
Can someone please help me.

 

[galactus]

Re: Hard Trig Problem sin(6x)=cos(9x)

You could try the addition formulas for sine and cosine. Using degrees, try some values starting with x=6.

There are 4 more up to x=90.

Starting with x=6, try increments of 24 up to x=90.

 

[mike10210]

Re: Hard Trig Problem sin(6x)=cos(9x)

Thank you for your help.