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प्रश्न
The value of sin2 29° + sin2 61° is
विकल्प
1
0
2 sin2 29°
2 cos2 61°
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उत्तर
The given expression is `sin^29°+sin^2 61°`
`sin^2 29°+sin^2 61°`.
=` sin^2 29°+(sin 61°)^2`
`= sin^2 29°+{sin(90°-29°)}^2`
`=sin^2 29°+(cos 29°)^2`
`= sin^2 29°+cos^2°29°`
`= 1`
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Choose the correct alternative:
cot θ . tan θ = ?
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Solution :
L.H.S. = cotθ + tanθ
= `cosθ/sinθ + sinθ/cosθ`
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= `1/(sinθ xx cosθ)` ............... `square`
= `1/sinθ xx 1/square`
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