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Prove or disprove the identity. If you find the identity is true, state the first line of the proof. If you find the identity is false, write the correct equation by replacing the right side.

sinxtanx = 1 + cos^2x/cosx

User Guri S
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Final answer:

After simplifying the right side of the equation using the Pythagorean identity, we find that the original identity sin(x)tan(x) = 1 + cos^2(x)/cos(x) is false, and the correct equation is sin(x)tan(x) = sin^2(x)/cos(x).

Step-by-step explanation:

To prove or disprove the identity sinxtanx = 1 + cos^2x/cosx, we will manipulate the left side of the equation and see if it simplifies to the right side. Starting with the left side, we have sinxtanx = sinx(sinx/cosx). Using the identity tanx = sinx/cosx, we can simplify further to sinx(sinx/(sinx/cosx)). Simplifying the expression inside the parentheses gives us sin^2x/cosx. Factoring out sin^2x from the numerator, we have sinx(sin^2x/cosx). Finally, using the identity sin^2x = 1 - cos^2x, we get sinx(1 - cos^2x/cosx), which simplifies to sinx - cos^2x. Therefore, the identity sinxtanx = 1 + cos^2x/cosx is false, and the correct equation is sinxtanx = sinx - cos^2x.

The student asked to prove or disprove the identity sin(x)tan(x) = 1 + cos2(x)/cos(x). To assess the identity, let us first simplify the right side by incorporating the Pythagorean identity sin2(x) + cos2(x) = 1. The thus becomes sin(x)sin(x)/cos(x) = sin2(x)/cos(x). We will substitute this into our original equation and see that the left side sin(x)tan(x) simplifies to sin2(x)/cos(x), which shows that the identity is false. To correct the equation, we replace the right side to get sin(x)tan(x) = sin2(x)/cos(x).

User Amir Ziarati
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