Prove that sin50-sin70+sin10=0

Steps to prove sin50-sin70+sin10=0

Take L.H.S sin50-sin70+sin10

=sin50-sin70+sin10

=sin50-(sin70-sin10)

[sinC-sinD=2cos(C+D)/2sin(C-D)/2]

=sin50-2cos(70+10)/2.sin(70-10)/2

=sin50-2cos40.sin30

=sin50-2cos40.1/2

=sin50-cos40

=sin(pi-40)-cos40

=cos40-cos40=0

=R.H.S

Hence sin50-sin70+sin10=0 is proved

Detail Information:- 

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