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Trigonometry--identity proof question,help

need help plz for Q)10 part b and c
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Reply 1
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Zacken
22
Original post by lil_jack
need help plz for Q)10 part b and c


What have you tried? For (b) multiply the LHS by 1+sin⁡θ1+sin⁡θ\frac{1 + \sin \theta}{1 + \sin \theta} so you get the denominator as you want and you get a difference of two squares in the numerator that you can Pythagoras and cancel with the denominator.

For (c) turn everything into sines and cosines and then make common denominators and then use a nice identity in the numerator.
cross multiply in b because one is plus one is minus so they cancel out and your answer is one. c is too hard i havent learnt tan yet
Reply 3
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Zacken
22
Original post by white.daniel
cross multiply in b because one is plus one is minus so they cancel out and your answer is one. c is too hard i havent learnt tan yet


No, that's incorrect.
Original post by Zacken
No, that's incorrect.


did they mean to write a plus on the left side becuase plus doesnt equal minus sign
Reply 5
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Zacken
22
Original post by white.daniel
did they mean to write a plus on the left side becuase plus doesnt equal minus sign


sigh, no, your logic is just wrong. You're doing B⇒AB \Rightarrow A when you should be doing A⇒BA \Rightarrow B
Reply 6
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Zacken
22
Original post by white.daniel
theres no a in the question, were looking at part b here

are you pulling my leg here?


No - guess you're another troll. Ignored and reported.

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