面积 y=x^4,x=y^7,1

解答

面积

y = x^{4}, x = y^{7}, 1

无解

求解步骤

对于

x = y^{7}

将

y

移到一边:

y = 7 x

f_{1} (x) = x^{4}

f_{2} (x) = 7 x

要找到相交点，解

f_{i} (x) = f_{j} (x)

x^{4} = 7 x : x \approx 0.00000 \dots, x \approx 1.00000 \dots

x^{4} = 1 : x = 1, x = - 1

7 x = 1 : x = 1

曲线没有界限

= 无解

\int 8 + 2 x - x^{2} d x

x \to 1 + lim (ln x^{2} - 1)

\int_{0}^{1} x 5 x + 4 d x

\int x^{2} + sin (x) d x

\int \frac{( x ^{3} )}{4 + x ^{2}} d x