How do you solve #2sinthetacostheta +costheta=0#?

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Answer 1 · 2017-05-17T18:09:55

#theta=pi/2+npi, 11pi/6+2npi, 7pi/6+2npi#

Factor out a #costheta#:

#(costheta)(2sintheta+1)=0#

Now solve for each of these:

#costheta=0#

This happens when #theta=pi/2+npi# where #n# is a whole number.

#2sintheta+1=0#

#sintheta=-1/2#

This happens at #theta=7pi/6+2npi# and #theta=11pi/6+2npi#