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If 6(sec^(2) 59^(@)-cot^(2)31^(@))-(2)/(...

If `6(sec^(2) 59^(@)-cot^(2)31^(@))-(2)/(3) sin90^(@)-3 tan^(2)56^(@)y tan^(2)34^(@)=(y)/(3)` then the value of y is :

A

`(8)/(5)`

B

`-(8)/(5)`

C

`(2)/(3)`

D

`(-2)/(3)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation given in the problem, we will follow a step-by-step approach: ### Step 1: Rewrite the equation The equation is given as: \[ 6(\sec^2 59^\circ - \cot^2 31^\circ) - \frac{2}{3} \sin 90^\circ - 3 \tan^2 56^\circ y \tan^2 34^\circ = \frac{y}{3} \] ### Step 2: Simplify \(\sin 90^\circ\) We know that \(\sin 90^\circ = 1\). Thus, we can rewrite the equation: \[ 6(\sec^2 59^\circ - \cot^2 31^\circ) - \frac{2}{3} - 3 \tan^2 56^\circ y \tan^2 34^\circ = \frac{y}{3} \] ### Step 3: Use trigonometric identities Using the identity \(\sec^2 \theta - \cot^2 \theta = 1\): \[ \sec^2 59^\circ - \cot^2 31^\circ = 1 \] So, we can substitute this into the equation: \[ 6(1) - \frac{2}{3} - 3 \tan^2 56^\circ y \tan^2 34^\circ = \frac{y}{3} \] ### Step 4: Simplify further This simplifies to: \[ 6 - \frac{2}{3} - 3 \tan^2 56^\circ y \tan^2 34^\circ = \frac{y}{3} \] ### Step 5: Find a common denominator To combine the constants, we convert \(6\) into a fraction with a denominator of \(3\): \[ 6 = \frac{18}{3} \] Thus, we have: \[ \frac{18}{3} - \frac{2}{3} - 3 \tan^2 56^\circ y \tan^2 34^\circ = \frac{y}{3} \] ### Step 6: Combine the fractions Combining the fractions gives: \[ \frac{16}{3} - 3 \tan^2 56^\circ y \tan^2 34^\circ = \frac{y}{3} \] ### Step 7: Clear the fractions Multiply the entire equation by \(3\) to eliminate the denominators: \[ 16 - 9 \tan^2 56^\circ y \tan^2 34^\circ = y \] ### Step 8: Rearrange the equation Rearranging gives: \[ 16 = y + 9 \tan^2 56^\circ y \tan^2 34^\circ \] Factoring out \(y\): \[ 16 = y(1 + 9 \tan^2 56^\circ \tan^2 34^\circ) \] ### Step 9: Solve for \(y\) Now, we can solve for \(y\): \[ y = \frac{16}{1 + 9 \tan^2 56^\circ \tan^2 34^\circ} \] ### Step 10: Calculate the value of \(y\) To find the exact value of \(y\), we need to calculate \(9 \tan^2 56^\circ \tan^2 34^\circ\). Using the values: - \(\tan 56^\circ \approx 1.4826\) - \(\tan 34^\circ \approx 0.6745\) Calculating: \[ \tan^2 56^\circ \approx 2.198 \] \[ \tan^2 34^\circ \approx 0.454 \] \[ 9 \tan^2 56^\circ \tan^2 34^\circ \approx 9 \times 2.198 \times 0.454 \approx 8.999 \] Thus, \[ y \approx \frac{16}{1 + 8.999} = \frac{16}{9.999} \approx 1.6 \] ### Final Value of \(y\) After simplification, we find: \[ y = \frac{16}{10} = \frac{8}{5} \] ### Conclusion The value of \(y\) is \(\frac{8}{5}\).
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