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(1+sin 2theta+cos 2theta)/(1+sin2 theta-...

`(1+sin 2theta+cos 2theta)/(1+sin2 theta-cos 2 theta)`=

A

`(1)/(2)tan theta`

B

`(1)/(2)cot theta`

C

`tan theta`

D

`cot theta`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the expression \((1 + \sin 2\theta + \cos 2\theta) / (1 + \sin 2\theta - \cos 2\theta)\), we will use trigonometric identities to simplify it step by step. ### Step 1: Substitute the identities We know that: \[ \sin 2\theta = 2\sin \theta \cos \theta \] \[ \cos 2\theta = \cos^2 \theta - \sin^2 \theta \] Substituting these identities into the expression gives us: \[ \frac{1 + 2\sin \theta \cos \theta + (\cos^2 \theta - \sin^2 \theta)}{1 + 2\sin \theta \cos \theta - (\cos^2 \theta - \sin^2 \theta)} \] ### Step 2: Simplify the numerator Now, let's simplify the numerator: \[ 1 + 2\sin \theta \cos \theta + \cos^2 \theta - \sin^2 \theta \] We can express \(1\) as \(\sin^2 \theta + \cos^2 \theta\): \[ \sin^2 \theta + \cos^2 \theta + 2\sin \theta \cos \theta + \cos^2 \theta - \sin^2 \theta \] This simplifies to: \[ 2\cos^2 \theta + 2\sin \theta \cos \theta \] ### Step 3: Simplify the denominator Now, let's simplify the denominator: \[ 1 + 2\sin \theta \cos \theta - (\cos^2 \theta - \sin^2 \theta) \] Again, substituting \(1\) as \(\sin^2 \theta + \cos^2 \theta\): \[ \sin^2 \theta + \cos^2 \theta + 2\sin \theta \cos \theta - \cos^2 \theta + \sin^2 \theta \] This simplifies to: \[ 2\sin^2 \theta + 2\sin \theta \cos \theta \] ### Step 4: Rewrite the expression Now we can rewrite our expression: \[ \frac{2\cos^2 \theta + 2\sin \theta \cos \theta}{2\sin^2 \theta + 2\sin \theta \cos \theta} \] ### Step 5: Factor out common terms We can factor out \(2\) from both the numerator and the denominator: \[ \frac{2(\cos^2 \theta + \sin \theta \cos \theta)}{2(\sin^2 \theta + \sin \theta \cos \theta)} \] This simplifies to: \[ \frac{\cos^2 \theta + \sin \theta \cos \theta}{\sin^2 \theta + \sin \theta \cos \theta} \] ### Step 6: Final simplification Now, we can express this as: \[ \frac{\cos^2 \theta + \sin \theta \cos \theta}{\sin^2 \theta + \sin \theta \cos \theta} \] This is the simplified form of the original expression. ### Final Answer Thus, the value of the expression \(\frac{1 + \sin 2\theta + \cos 2\theta}{1 + \sin 2\theta - \cos 2\theta}\) is: \[ \frac{\cos^2 \theta + \sin \theta \cos \theta}{\sin^2 \theta + \sin \theta \cos \theta} \]
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Knowledge Check

  • (1+sin2theta+cos2theta)/(1+sin2theta-cos2theta) =

    A
    `1/2tantheta`
    B
    `1/2cottheta`
    C
    `tantheta`
    D
    `cottheta`
  • Similar Questions

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