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प्रश्न
If cos θ = `24/25`, then sin θ = ?
उत्तर
cos θ = `24/25` ......[Given]
We know that,
sin2θ + cos2θ = 1
∴ `sin^2theta + (24/25)^2` = 1
∴ `sin^2theta + 576/625` = 1
∴ sin2θ = `1 - 576/625`
∴ sin2θ = `(625 - 576)/625`
∴ sin2θ = `49/625`
∴ sin θ = `7/25` ......[Taking square root of both sides]
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संबंधित प्रश्न
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Activity:
L.H.S = `square`
= `square/sintheta + sintheta/costheta`
= `(cos^2theta + sin^2theta)/square`
= `1/(sintheta*costheta)` ......`[cos^2theta + sin^2theta = square]`
= `1/sintheta xx 1/square`
= `square`
= R.H.S
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