SOLUTION: The wings on an airplane are usually angled upward relative to the body, fuselage, of the aircraft. This is known as dihedral, and makes the aircraft more stable in flight, especia

Algebra ->  Trigonometry-basics -> SOLUTION: The wings on an airplane are usually angled upward relative to the body, fuselage, of the aircraft. This is known as dihedral, and makes the aircraft more stable in flight, especia      Log On


   



Question 617270: The wings on an airplane are usually angled upward relative to the body, fuselage, of the aircraft. This is known as dihedral, and makes the aircraft more stable in flight, especially during turbulence. Some aircraft hve double dihedral. Suppose that wing is designed as shown, with an initial dihedral angle of x for the first 6ft and an additional angle of x for the next 6 feet. Show that h2= 6sinx(1+2cosx).
... I have no idea where to start with this question.

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
That angle x must be very small, but I will draw it larger to make it easier to see.
I will put x's inside the angles that measure x.
I will draw a blue plane body and wings.
I'll add a green line continuing the line of the wing as it comes out of the body of the plane.
I'll add extra lines to make triangles, drawing vertical lines in red, horizontal ones in black.
Triangles ABD and BCF are right triangles. AB=BC=6 feet.
For triangle ABD, with the angle at A measuring x,
BD=6%2Asinx
For triangle BCF, with the angle at B measuring 2x,
CF=6%2Asin%282x%29
Using trigonomrtric identities,
CF=6%2Asin%282x%29=6%2A2sinx%2Acosx
The height of the tip of the wing over the body of the airplane is
CE=CF%2BFE=CF%2BBD=6%2A2sinx%2Acosx%2B6%2Asinx=6%2Asinx%281%2B2cosx%29
CE=highlight%286%2Asinx%281%2B2cosx%29%29