Two sides of a triangle are 12m and 15m in length and the angle between them is increasing at a rate of 2 deg/min. Find the rate at which the area of the triangle is increasing when the angle between their sides of fixed length is 60 deg?
2 answers
My answer is 155m^2/min i just wanted to confirm if im doing it right.
A = (1/2)(12)(15)sin x , where x is the angle in radians
dA/dt = 90 cosx dx/dt
given: dx/dt = 2π/180 = π/90
so when x = π/3
dA/dt = 90(cos π/3)(π/90)
= (90)(1/2)(π/90) = π/2
How did you get 155 ? Remember, you have to use radians.
dA/dt = 90 cosx dx/dt
given: dx/dt = 2π/180 = π/90
so when x = π/3
dA/dt = 90(cos π/3)(π/90)
= (90)(1/2)(π/90) = π/2
How did you get 155 ? Remember, you have to use radians.