Help I'm stuck on a trig question
if sin(x)= 3/5 and cos(y)=5/13 find the exact value of tan(x+y) (hint, you shouldn't have to evaluate x and y themselves)

Question

Help I'm stuck on a trig question
if sin(x)= 3/5 and cos(y)=5/13 find the exact value of tan(x+y) (hint, you shouldn't have to evaluate x and y themselves)

michele_laino · Answer

please you have to apply this formula:
$$\tan(x+y)=\frac{ \tan x+\tan y }{ 1-\tan x*\tan y }$$
in order to that, you have to calculate cos(x) and sin (y), so do you know in whic quadrant are x and y respectively?

michele_laino · Answer

sorry, ...in which quadrants....

michele_laino · Answer

@dumbcow  thanks!

anonymous · Answer

Is it 5/13? Sorry if I'm wrong :/

cwrw238 · Answer

you can get tan x and tan y from the right angled triangles withe sides 3-4-5 and 5-12-13

cwrw238 · Answer

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