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Maharashtra State BoardSSC (English Medium) 10th Standard

Tan^2θ – sin^2θ = tan^2θ × sin^2θ. For proof of this complete the activity given below. Activity: L.H.S. = square = square (1 – (sin^2θ)/(tan^2θ)) = tan^2θ (1 – square/((sin^2θ)/(cos^2θ)))

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Question

tan2θ – sin2θ = tan2θ × sin2θ. For proof of this complete the activity given below.

Activity:

L.H.S. = `square`

= `square (1 - (sin^2θ)/(tan^2θ))`

= `tan^2θ (1 - square/((sin^2θ)/(cos^2θ)))`

= `tan^2θ (1 - (sin^2θ)/1 xx (cos^2θ)/square)`

= `tan^2θ (1 - square)`

= `tan^2θ xx square`   ...[1 – cos2θ = sin2θ]

= R.H.S.

Activity
Theorem
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Solution

L.H.S. = \[\boxed{\text{tan}^2θ - \text{sin}^2θ}\] 

= \[\boxed{\text{tan}^2θ} \left(1 - \frac{\text{sin}^2θ}{\text{tan}^2θ}\right)\]

= \[\tan^2\theta\left(1-\frac{\boxed{\sin^2\theta}}{\frac{\sin^2\theta}{\cos^2\theta}}\right)\]

= \[\tan^{2}\theta\left(1-\frac{\sin^{2}\theta}{1}\times\frac{\cos^{2}\theta}{\boxed{\sin^{2}\theta}}\right)\]

= \[\text{tan}^2θ \left(1 - \boxed{\text{cos}^2θ}\right)\]

= \[\text{tan}^2θ × \boxed{\text{sin}^2θ}\]   ...[1 – cos2θ = sin2θ]

= R.H.S.

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Chapter 6: Trigonometry - Exercise

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Activity:

L.H.S. = `square`

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= `1/(sinθ.cosθ)`   ...`[cos^2θ + sin^2θ = square]`

= `1/(sinθ) xx 1/square`

= `square`

= R.H.S.


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