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If cos^(2)30^(@)+cos^(2)45^(@)+cos^(2)60...

If `cos^(2)30^(@)+cos^(2)45^(@)+cos^(2)60^(@)=x`, then find the value of 'x'

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To find the value of \( x \) in the equation \( \cos^2 30^\circ + \cos^2 45^\circ + \cos^2 60^\circ = x \), we will calculate each term step by step. ### Step 1: Calculate \( \cos^2 30^\circ \) We know that: \[ \cos 30^\circ = \frac{\sqrt{3}}{2} \] Now, squaring this value: \[ \cos^2 30^\circ = \left(\frac{\sqrt{3}}{2}\right)^2 = \frac{3}{4} \] ### Step 2: Calculate \( \cos^2 45^\circ \) We know that: \[ \cos 45^\circ = \frac{1}{\sqrt{2}} = \frac{\sqrt{2}}{2} \] Now, squaring this value: \[ \cos^2 45^\circ = \left(\frac{1}{\sqrt{2}}\right)^2 = \frac{1}{2} \] ### Step 3: Calculate \( \cos^2 60^\circ \) We know that: \[ \cos 60^\circ = \frac{1}{2} \] Now, squaring this value: \[ \cos^2 60^\circ = \left(\frac{1}{2}\right)^2 = \frac{1}{4} \] ### Step 4: Sum the values Now we can sum all the calculated values: \[ x = \cos^2 30^\circ + \cos^2 45^\circ + \cos^2 60^\circ \] Substituting the values we found: \[ x = \frac{3}{4} + \frac{1}{2} + \frac{1}{4} \] ### Step 5: Find a common denominator The common denominator for \( 4 \) and \( 2 \) is \( 4 \). We can rewrite \( \frac{1}{2} \) as \( \frac{2}{4} \): \[ x = \frac{3}{4} + \frac{2}{4} + \frac{1}{4} \] ### Step 6: Combine the fractions Now, we can combine the fractions: \[ x = \frac{3 + 2 + 1}{4} = \frac{6}{4} \] ### Step 7: Simplify the result Finally, simplifying \( \frac{6}{4} \): \[ x = \frac{3}{2} \] Thus, the value of \( x \) is: \[ \boxed{\frac{3}{2}} \]
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