Prévia do material em texto
**Explicação**: A integral é:
\[
\int_0^1 (1 - x^2) \, dx = \left[ x - \frac{x^3}{3} \right]_0^1 = \left( 1 - \frac{1}{3} \right) =
\frac{2}{3}
\]
37. **Problema 37**: Calcule \( \int_0^{\pi/2} \sin^2(x) \, dx \).
a) \( \frac{\pi}{4} \)
b) \( \frac{\pi}{6} \)
c) \( \frac{\pi}{3} \)
d) \( \frac{\pi}{2} \)
**Resposta**: a) \( \frac{\pi}{4} \)
**Explicação**: Usando a identidade \( \sin^2(x) = \frac{1 - \cos(2x)}{2} \):
\[
\int_0^{\pi/2} \sin^2(x) \, dx = \frac{1}{2} \left[ x - \frac{\sin(2x)}{2} \right]_0^{\pi/2} =
\frac{1}{2} \left( \frac{\pi}{2} - 0 \right) = \frac{\pi}{4}
\]
38. **Problema 38**: Calcule o limite \( \lim_{x \to 0} \frac{x^2}{\sin(x)} \).
a) \( 0 \)
b) \( 1 \)
c) \( \infty \)
d) \( -1 \)
**Resposta**: a) \( 0 \)
**Explicação**: Usando a regra de L'Hôpital:
\[
\lim_{x \to 0} \frac{x^2}{\sin(x)} = \lim_{x \to 0} \frac{2x}{\cos(x)} = 0
\]
39. **Problema 39**: Calcule \( \int_0^1 (x^5 - 3x^4 + 3x^3 - x^2) \, dx \).
a) \( 0 \)
b) \( \frac{1}{6} \)
c) \( \frac{1}{4} \)
d) \( \frac{1}{3} \)
**Resposta**: a) \( 0 \)
**Explicação**: A integral é:
\[
\int_0^1 (x^5 - 3x^4 + 3x^3 - x^2) \, dx = \left[ \frac{x^6}{6} - \frac{3x^5}{5} + \frac{3x^4}{4}
- \frac{x^3}{3} \right]_0^1 = \left( \frac{1}{6} - \frac{3}{5} + \frac{3}{4} - \frac{1}{3} \right) = 0
\]
40. **Problema 40**: Calcule \( \int_0^1 (2x^2 - 4x + 2) \, dx \).
a) \( 0 \)
b) \( 1 \)
c) \( \frac{1}{3} \)
d) \( 2 \)
**Resposta**: b) \( 1 \)
**Explicação**: A integral é:
\[
\int_0^1 (2x^2 - 4x + 2) \, dx = \left[ \frac{2x^3}{3} - 2x^2 + 2x \right]_0^1 = \left( \frac{2}{3}
- 2 + 2 \right) = \frac{2}{3}
\]
41. **Problema 41**: Calcule \( \int \frac{1}{1+x^2} \, dx \).
a) \( \tan^{-1}(x) + C \)
b) \( \frac{1}{1+x} + C \)
c) \( \ln(1+x^2) + C \)
d) \( \frac{1}{2} \tan^{-1}(x) + C \)
**Resposta**: a) \( \tan^{-1}(x) + C \)
**Explicação**: A integral é:
\[
\int \frac{1}{1+x^2} \, dx = \tan^{-1}(x) + C
\]
42. **Problema 42**: Calcule \( \lim_{x \to 0} \frac{\ln(1+x)}{x} \).
a) \( 0 \)
b) \( 1 \)
c) \( \infty \)
d) \( -1 \)
**Resposta**: b) \( 1 \)
**Explicação**: Usando a regra de L'Hôpital:
\[
\lim_{x \to 0} \frac{\ln(1+x)}{x} = \lim_{x \to 0} \frac{\frac{1}{1+x}}{1} = 1
\]
43. **Problema 43**: Calcule \( \int_0^1 (3x^2 - 4x + 1) \, dx \).
a) \( 0 \)
b) \( \frac{1}{3} \)
c) \( \frac{1}{6} \)
d) \( 1 \)
**Resposta**: a) \( 0 \)
**Explicação**: A integral é:
\[
\int_0^1 (3x^2 - 4x + 1) \, dx = \left[ x^3 - 2x^2 + x \right]_0^1 = (1 - 2 + 1) = 0
\]
44. **Problema 44**: Calcule \( \int_0^{\pi/2} \sin^3(x) \, dx \).
a) \( \frac{3}{8} \)
b) \( \frac{1}{4} \)
c) \( \frac{1}{2} \)
d) \( \frac{1}{3} \)
**Resposta**: a) \( \frac{3}{8} \)
**Explicação**: Usando a identidade \( \sin^3(x) = \sin(x)(1 - \cos^2(x)) \):
\[
\int_0^{\pi/2} \sin^3(x) \, dx = \int_0^{\pi/2} \sin(x) - \sin(x)\cos^2(x) \, dx = \frac{3}{8}