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Find the exact area of the surface obtained by rotating the

curve about the x-axis. y = sqrt(1 + e^x) , 0 ≤ x ≤ 8

User Josep
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Final answer:

To find the exact area of the surface obtained by rotating the curve about the x-axis, we can use the formula for the surface area of a curve rotated about the x-axis. The formula is given by: A = 2π ∫[a,b] y(x) sqrt(1 + (y'(x))^2) dx, where y(x) is the function representing the curve and y'(x) is the derivative of y(x) with respect to x. In this case, y(x) = sqrt(1 + e^x) and the limits of integration are from 0 to 8.

Step-by-step explanation:

To find the exact area of the surface obtained by rotating the curve about the x-axis, we can use the formula for the surface area of a curve rotated about the x-axis. The formula is given by: A = 2π ∫[a,b] y(x) sqrt(1 + (y'(x))^2) dx, where y(x) is the function representing the curve and y'(x) is the derivative of y(x) with respect to x. In this case, y(x) = sqrt(1 + e^x) and the limits of integration are from 0 to 8.

To evaluate the integral, we first need to find the derivative of y(x). The derivative of y(x) = sqrt(1 + e^x) with respect to x can be found using the chain rule. Taking the derivative, we get y'(x) = (e^x)/(2sqrt(1 + e^x)).

Substituting the expression for y(x) and y'(x) into the formula, we have A = 2π ∫[0,8] sqrt(1 + e^x) sqrt(1 + (e^x/2sqrt(1 + e^x))^2) dx.

Unfortunately, evaluating this integral analytically is quite challenging. However, it can be evaluated numerically using approximation methods such as numerical integration or numerical methods like Simpson's rule or trapezoidal rule.

User Comdiv
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