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प्रश्न
Without using trigonometric tables, prove that:
sin248° + sin242° = 1
उत्तर
LHS = sin248° + sin242°
= sin2 (`90^circ - 42^circ`) + sin2 `42^circ`
= `cos^2 42^circ+ sin^2 42^circ`
= 1
= RHS
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