You solved the problem correctly, well done. However, you did it the hard way in my opinion. It is worthy of note that cot(θ) = x/40. Differentiating both sides of this equation with respect to θ gives - csc^2(θ) = 1/40·dx/dθ --> - (80/40)^2 = 1/40·dx/dθ. Taking the reciprocal of this expression gives: - 1/4 = 40·dθ/dx. Therefore, dθ/dx = - 1/160. By the chain rule dθ/dt = dθ/dx·dx/dt, it follows that dθ/dt = (- 1/160)(3/1) = - 3/160 rad/s ◼
Thank you Mr. Barnes! I had just one question. Doesn't the x^2 from the denominator and the one from the numerator cancel out? In that case you could skip computing the value of x, right? Thanks, for related rates I would be lost without youtube :).
kite, at a height of 42 ft is moving horizontally at a rate of 5 ft/s away from the boy whoflies it. How fast is the cord being released when there are 63.7809 ft out?
I can't thank you enough Mr. Barnes! your method is so much easier than the one I learned. Thank you always for helping
Glad I could help!
You solved the problem correctly, well done. However, you did it the hard way in my opinion. It is worthy of note that cot(θ) = x/40. Differentiating both sides of this equation with respect to θ gives - csc^2(θ) = 1/40·dx/dθ --> - (80/40)^2 = 1/40·dx/dθ.
Taking the reciprocal of this expression gives: - 1/4 = 40·dθ/dx. Therefore, dθ/dx = - 1/160.
By the chain rule dθ/dt = dθ/dx·dx/dt, it follows that dθ/dt = (- 1/160)(3/1) = - 3/160 rad/s ◼
Thank you Mr. Barnes! I had just one question. Doesn't the x^2 from the denominator and the one from the numerator cancel out? In that case you could skip computing the value of x, right? Thanks, for related rates I would be lost without youtube :).
THANK YOU SO MUCH. I'VE GOT THE SAME EXACT QUESTION, EXCEPT FOR THE GIVEN VALUES OF COURSE
At 1:44 shouldn’t that be dx/dt?
Yes
kite, at a height of 42 ft is moving horizontally at a rate of 5 ft/s away from the boy whoflies it. How fast is the cord being released when there are 63.7809 ft out?
Good video but confused the shit out of me when you put dx/dy=3 m/sec instead it's dx/dt
Thank you for this video! It helped me a lot.
Very good 🙏🙏🙏🙏🙏
Thank You!