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Find the value of: 2("sin"^(6)x+cos^(...

Find the value of:
`2("sin"^(6)x+cos^(6)x)-3("sin"^(4)x+cos^(4)x)+2`.

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To solve the expression \( 2(\sin^6 x + \cos^6 x) - 3(\sin^4 x + \cos^4 x) + 2 \), we will simplify it step by step. ### Step 1: Use the identity for \( \sin^6 x + \cos^6 x \) We can use the identity: \[ a^3 + b^3 = (a + b)(a^2 - ab + b^2) \] where \( a = \sin^2 x \) and \( b = \cos^2 x \). Thus, \[ \sin^6 x + \cos^6 x = (\sin^2 x + \cos^2 x)((\sin^2 x)^2 - \sin^2 x \cos^2 x + (\cos^2 x)^2) \] Since \( \sin^2 x + \cos^2 x = 1 \), we have: \[ \sin^6 x + \cos^6 x = 1 \cdot ((\sin^2 x)^2 - \sin^2 x \cos^2 x + (\cos^2 x)^2) \] Now, we can simplify \( (\sin^2 x)^2 + (\cos^2 x)^2 \): \[ (\sin^2 x)^2 + (\cos^2 x)^2 = \sin^4 x + \cos^4 x \] So, \[ \sin^6 x + \cos^6 x = \sin^4 x + \cos^4 x - \sin^2 x \cos^2 x \] ### Step 2: Substitute back into the original expression Now substitute this back into the original expression: \[ 2(\sin^6 x + \cos^6 x) = 2(\sin^4 x + \cos^4 x - \sin^2 x \cos^2 x) \] \[ = 2\sin^4 x + 2\cos^4 x - 2\sin^2 x \cos^2 x \] Now, substituting this into the expression: \[ 2\sin^4 x + 2\cos^4 x - 2\sin^2 x \cos^2 x - 3(\sin^4 x + \cos^4 x) + 2 \] ### Step 3: Combine like terms Now combine the terms: \[ (2\sin^4 x - 3\sin^4 x) + (2\cos^4 x - 3\cos^4 x) - 2\sin^2 x \cos^2 x + 2 \] \[ = -\sin^4 x - \cos^4 x - 2\sin^2 x \cos^2 x + 2 \] ### Step 4: Use the identity for \( \sin^4 x + \cos^4 x \) We can use the identity: \[ \sin^4 x + \cos^4 x = (\sin^2 x + \cos^2 x)^2 - 2\sin^2 x \cos^2 x = 1 - 2\sin^2 x \cos^2 x \] Substituting this back: \[ -\left(1 - 2\sin^2 x \cos^2 x\right) - 2\sin^2 x \cos^2 x + 2 \] \[ = -1 + 2\sin^2 x \cos^2 x - 2\sin^2 x \cos^2 x + 2 \] \[ = -1 + 2 \] \[ = 1 \] ### Final Result Thus, the value of the expression is: \[ \boxed{1} \]
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