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प्रश्न
Evaluate cos 48° − sin 42°
उत्तर
We have to find cos 48° − sin 42°
Since `cos (90^@ - theta) = sin theta` So
`cos 48^@ - sin 42^@ = cos (90^@ - 42^@) - sin 42^@`
`= sin 42^@ - sin 42^@`
= 0
So value of `cos 48^@ - sin 42^@` is 0
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