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The value of 2sin2 π/6 + cosec2 7π/6 x cos2 π/3 is m/m - 1. Find the value of 'm'. |
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Answer» 2sin2 \(\cfrac{\pi}6\) + cosec2 \(\cfrac{7\pi}6\) cos2 \(\cfrac{\pi}3\) = 2(sin \(\cfrac{\pi}6\))2 + (cosec (π + \(\cfrac{\pi}6\)))2 (cos\(\cfrac{\pi}3\))2 = 2 (\(\cfrac{1}2\))2 + (-cosec\(\cfrac{\pi}6\))2 (\(\cfrac{1}2\))2 (\(\because\) sin \(\cfrac{\pi}6\) = cos \(\cfrac{\pi}3\) = \(\cfrac{1}2\)) = \(\cfrac{2}4\) + (-2)2 x \(\cfrac{1}4\) (\(\because\) cosec \(\cfrac{\pi}6\) = \(\cfrac1{sin{\cfrac{\pi}6}}\) = \(\cfrac1{{\cfrac{1}2}}\) = 2) = \(\cfrac{1}2\) + 4 x \(\cfrac{1}4\) = \(\cfrac{1}2\) + 1 = \(\cfrac{3}2\) = \(\cfrac{3}{3-1}\) ∴ m = 3 (by comparing) |
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