Given that. sin 2x = cos (3x - 10), find tanx

2x = 90 -(3x -10)
2x = 90 -3x + 10
2x = -3x + 100
2x + 3x = -3x + 3x + 100
5x = 100
x = 20
tanx = sin/cos
tan = sin40/cos50
Is that correct

your x = 20 if x is in degrees

so tan x = tan20, which is not a rational number.
my calculator says: .36397...

why are you saying tanx = sin40/cos50 ??
tanx = sinx/cosx = sin20/cos20 = .36397...

Reiny is right to wonder when you wrote:

tan x = sin 40 / cos 50

because

sin( 4​0° ) = cos( 90° − 40° ) = cos 50°

so

sin 40° / cos 50°= cos 50° / cos 50° = 1

To find the value of tan(x), we first need to find the value of x from the equation sin(2x) = cos(3x - 10).

You correctly solved the equation and found that x = 20.

Now, to find tan(x), we can substitute the value of x into the formula tan(x) = sin(x)/cos(x).

However, it seems like there was a mistake in your final step. The correct values should be sin(40) and cos(50), not sin(40)/cos(50).

So, the correct way to calculate tan(x) using the given value of x = 20 is:

tan(20) = sin(20)/cos(20)

You can use a scientific calculator or reference table to find the numerical values of sin(20) and cos(20) and then divide them to get the value of tan(20).