i want to check my answer if possible
Your work is incorrect, with mistakes on almost every line.
Line 2: You multiplied both fractions by the same expression. You need to multiply each fraction by something different.
Line 3: cosx - cosx = 0 not 2cosx.
Line 5: cosx != 1 - sinx
Line 6: sin^2(x) - 1 != -(1 + sin^2(x))
Line 7: -(1 + sin^2(x)) != sin^2(x) - 1
Line 8: sin^2(x) - 1 != sinx
thanks very much
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