Apply Weierstrass substitution: Use the Weierstrass substitution to simplify the integral. Let t=tan(2x), then sin(x)=1+t22t and dx=1+t22dt.
Substitute sin(x) and dx: Substitute sin(x) and dx in the integral.∫1−sinx1dx=∫1−1+t22t1⋅1+t22dt
Simplify the integrand: Simplify the integrand. ∫1−1+t22t1⋅1+t22dt=∫1+t2−2t1+t2⋅1+t22dt=∫1−t22dt
Decompose into partial fractions: Decompose the integrand into partial fractions. 1−t22 can be written as 1−tA+1+tB.Solving for A and B, we get A=1 and B=1.
Write in terms of partial fractions: Write the integral in terms of the partial fractions. \int\frac{\(2\)}{\(1\) - t^\(2\)}\,dt = \int\frac{\(1\)}{\(1\) - t}\,dt + \int\frac{\(1\)}{\(1\) + t}\,dt
Integrate each term separately: Integrate each term separately.\(\newline∫1−t1dt=−ln∣1−t∣+C1∫1+t1dt=ln∣1+t∣+C2
Combine the two integrals: Combine the two integrals. ∫1−t22dt=−ln∣1−t∣+ln∣1+t∣+C=ln∣1+t∣−ln∣1−t∣+C
Substitute back for t: Substitute back for t = tan(2x).ln∣1+tan(2x)∣−ln∣1−tan(2x)∣+C=ln∣(1−tan(2x))(1+tan(2x))∣+C
Simplify using trigonometric identities: Simplify the expression using trigonometric identities.\ln\left|\frac{\(1\) + \tan(\frac{x}{\(2\)})}{\(1\) - \tan(\frac{x}{\(2\)})}\right| + C = \ln\left|\frac{(\(1\) + \tan(\frac{x}{\(2\)}))^\(2\)}{(\(1\) - \tan(\frac{x}{\(2\)}))(\(1\) + \tan(\frac{x}{\(2\)}))}\right| + C\(\newline= \ln\left|\frac{(1 + \tan(\frac{x}{2}))^2}{1 - \tan^2(\frac{x}{2})}\right| + C= \ln\left|\frac{1 + \sin(x)}{1 - \sin(x)}\right| + C
Check final expression: Check if the final expression is correct.The final expression ln∣∣(1−sin(x))(1+sin(x))∣∣+C is the antiderivative of (1−sinx)1, which answers the question prompt.
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