Below is an attempt to simplify the statement $\cos^4(t) - \sin^4(t)$. The attempt below has a mistake. Identify the initial mistake and explain how to fix only the initial mistake. $\cos^4(t) - \sin^4(t) = (\cos^2(t) - \sin^2(t))(\cos^2(t) + \sin^2(t))$ $= (\cos^2(t) - \sin^2(t))(1)$ $= (\cos^2(t) - (\cos^2(t) - 1))(1)$ $= (\cos^2(t) - \cos^2(t) + 1)(1)$ $= (0 + 1)(1)$ $= 1$
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The given simplification steps are: 1. $\cos^4(t) - \sin^4(t) = (\cos^2(t) - \sin^2(t))(\cos^2(t) + \sin^2(t))$ 2. $= (\cos^2(t) - \sin^2(t))(1)$ 3. $= (\cos^2(t) - (\cos^2(t) - 1))(1)$ 4. $= (\cos^2(t) - \cos^2(t) + 1)(1)$ 5. $= (0 + 1)(1)$ 6. $= 1$ Let's Show more…
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