What is the volume of the solid whose cross-sections are equilateral triangles perpendicular to the x -axis and with bases on the region bounded by curves y = x 2 + 1 , x = 1 , and x -axis and the y -axis ?
The volume is the sum of all the areas of the cross-sections. [tex]V = \int_a^b A(x) dx[/tex]
The Area is the area of an equilateral triangle, where the length of the base is distance from curve 'x^2 + 1' and x-axis. The height of an equilateral triangle is [tex]\frac{\sqrt{3}}{2} b = \frac{\sqrt{3}}{2} (x^2 +1)[/tex]
Therefore Area of triangle is: [tex]A(x) = \frac{1}{2} b h = \frac{\sqrt{3}}{4} (x^2 + 1)^2[/tex]