Question

A rain gutter is to be constructed from a metal sheet of width 30 cm by bending up one-third of the sheet on each side through an angle of θ.
a. Show that the cross-sectional area of the gutter is modeled by the function A(θ) = 100 sinθ + 100 sinθ cosθ.
b. For what angle θ is the largest cross-sectional area achieved?

Answer 1

Sorry for the bad quality of the picture.I did not have a better cam.Anyway the solution is in the picture below.

Answer 2

Thank you so much!

Answer 3

Yw.