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प्रश्न
`1+((tan^2 theta) cot theta)/(cosec^2 theta) = tan theta`
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उत्तर
LHS = `((1+ tan^2 theta) cot theta)/ (cosec^2 theta) `
= ` (sec^2 theta cot theta)/(cosec^2 theta )`
= `(1/cos^2thetaxxcos theta/sin theta)/(1/sin^2 theta)`
= `1/(cos theta sin theta) xx sin^2 theta`
= `sintheta/costheta`
= ` tan theta`
= RHS
Hence, LHS = RHS
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Solution:
In Δ ABC, ∠ABC = 90°, ∠C = θ°
AB2 + BC2 = `square` .....(Pythagoras theorem)
Divide both sides by AC2
`"AB"^2/"AC"^2 + "BC"^2/"AC"^2 = "AC"^2/"AC"^2`
∴ `("AB"^2/"AC"^2) + ("BC"^2/"AC"^2) = 1`
But `"AB"/"AC" = square and "BC"/"AC" = square`
∴ `sin^2 theta + cos^2 theta = square`
