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Prove that 2sin² π/6cos²π/3=3/2prove that..I need Quality answer please don't post unnecessary Answer and don't spam..​

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\huge\bf\red{\underline{\underline{Solution}}}

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TAKING L.H.S

\bold{2sin²}\dfrac{π}{6}\bold{+\:cosec²\:}\dfrac{7π}{6}\bold{cos²}\dfrac{π}{3}

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putting π = 180°

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= \bold{2sin²}\dfrac{180}{6}\bold{+\:cosec²}\dfrac{7\:×\:180}{6}\bold{cos²}]\dfrac{180}{3}

=\bold{2sin² \:30° \:+ cosec² \:210°\:cos² \:60}

=\bold{2(<klux>SIN</klux>\:30°)²\:+\:(cosec\:210°) \: (cos\:60°)²}

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Here,

\bold{sin\:30°\:=}\dfrac{<klux>1</klux>}{2}& \bold{sin\:cos\:60°=}\dfrac{1}{2}

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For cosec 210°

⠀⠀⠀⠀⠀⠀let's first calculate sin 210°

⠀⠀⠀⠀⠀⠀sin 210° = \bold{sin\:(180+30)}

⠀⠀⠀⠀⠀⠀= \bold{- \:sin 30°}

⠀⠀⠀⠀⠀⠀= \dfrac{-1}{2}

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So,

cosec 210° = \dfrac{1}{sin\:210°}

= \dfrac{1}{-1}=\dfrac{2}{-1}= - 2

\text{\large\underline{\red{putting\: values\: in \:equation}}}

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\bold{=\:2(sin\:30°)2 \:+ \:(cosec\:210°)? \:(cos\: 60°)²}

⠀⠀⠀⠀⠀= 2 \dfrac{1²}{2}+\bold{(-2)²}\dfrac{1²}{2}

⠀⠀⠀⠀⠀⠀⠀\bold{=\:2\:×}\dfrac{1}{2}+ 4 ×\dfrac{1}{2}

⠀⠀⠀⠀⠀⠀= \dfrac{1}{2} + 1

⠀⠀⠀⠀⠀⠀= \dfrac{1}{2} + 1

⠀⠀⠀⠀⠀⠀= \dfrac{3}{2}

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⠀⠀⠀⠀⠀⠀\bold{= \:R.H.S}

⠀⠀⠀⠀⠀⠀\text{\large\underline{\red{Hence\:proved}}}

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