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प्रश्न
If sin x = cos y, then x + y = 45° ; write true of false
विकल्प
True
False
उत्तर
sin x = cosy = sin`(x/2 – y )`
if x and y are acute angles,
x = `(x)/(2) – y`
x + y = `(x)/(2)`
∴ x + y = 45° is false.
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