If 3‾√ cot2θ – 4 cot θ + 3‾√ = 0, then find the value of cot2 θ + tan2θ. (2013) Solution:

Answer: The value of cot⁡2θ+tan⁡2θ\cot^2 \theta + \tan^2\theta is 103\frac{10}{3}.

Step-by-step solution

Step 1: Solve the quadratic equation for cot θ

We are given a quadratic equation in terms of cot⁡θ\cot\theta. We can solve this quadratic equation for cot⁡θ\cot\theta using the quadratic formula, where a=3a = \sqrt{3}, b=−4b = -4, and c=3c = \sqrt{3}.

Step 2: Apply the quadratic formula

Substitute the values of aa, bb, and cc into the quadratic formula: x=−b±b2−4ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}. This will give us the possible values for cot⁡θ\cot\theta.

Step 3: Simplify the expression for cot θ

Simplify the expression under the square root and then calculate the two possible values for cot⁡θ\cot\theta. This leads to two distinct solutions.

Step 4: Calculate the values of cot θ

Further simplify the two values of cot⁡θ\cot\theta. We rationalize the denominators by multiplying the numerator and denominator by 3\sqrt{3} where necessary.

Step 5: Calculate cot²θ and tan²θ for each case

For each value of cot⁡θ\cot\theta, we calculate cot⁡2θ\cot^2\theta and then find tan⁡θ\tan\theta using the identity tan⁡θ=1cot⁡θ\tan\theta = \frac{1}{\cot\theta}, and subsequently tan⁡2θ\tan^2\theta.

Step 6: Find the value of cot²θ + tan²θ

Finally, add the calculated values of cot⁡2θ\cot^2\theta and tan⁡2θ\tan^2\theta. Both cases yield the same result.

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