Some fundamental theory of calc 2 questions.

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I want to evaluate these integrals. I think I understand it, but I just wanted to check:

  1. $$\int_{-1}^1 x^{100} dx$$ $$\frac{1^{101}}{101} - \frac{-1^{101}}{101}$$ $$= \frac{1}{101} + \frac{1}{101} = \frac{2}{101}$$

  2. $$\int_{1}^9 \sqrt{x} dx$$ $$\frac{2}{3} \cdot 9^{\frac{3}{2}} - \frac{2}{3}$$ $$ = 18 - \frac{2}{3}$$ $$17 \frac{1}{3}$$

  3. $$\int_{1}^8 x^{\frac{-2}{3}} dx$$ So an antiderivative we can use is: $F(x) = \frac{x^{\frac{1}{3}}}{3}$ $$ \frac{8^{\frac{1}{3}}}{3} - \frac{1^{\frac{1}{3}}}{3}$$ $$ = \frac{2}{3} - \frac{1}{3} = \frac{1}{3}$$

  4. $$\int_{\frac{\pi}{6}}^\pi \sin \theta dx$$ $$ - \cos \pi - -\cos \frac{\pi}{6} $$ $$ = 1 + \frac{\sqrt{3}}{2}$$ $$= \frac{2 + \sqrt{3}}{2}$$

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As @littleO points out, the antiderivative of part 3 is incorrect.

$$\int_{1}^8 x^{-2/3} dx = \left[ \frac{x^{1/3}}{1/3} \right]_1^8 = [3\sqrt[3]{x}]_1^8 = 3(2-1) = 3$$

The rest is correct.