Recent content by Hind head

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You need to check back for mistakes. You have been given that the answer is Θ = 24.9 degrees. Have you tried plugging this into your equation t1 + t2 = (750/cosΘ) + (250(1.6sinΘ - 0.8))/(cosΘ) to see if this gives the answer 862 seconds

So you now have t1 + t2 = (750/cosΘ) + (250(1.6sinΘ - 0.8))/(cosΘ) To find the derivative of time with respect to θ, or dt/dθ you need to apply the rules of derivation (sometimes called differentiation rules). Its easier now to call the total time t, it just makes things look clearer. So you...

At the optimum angle the change in the total time taken for a small change in angle will be zero, so dt/dΘ = 0