tutorinseoul Posted March 22, 2017 Report Share Posted March 22, 2017 (edited) Hi! I like this question as it deals with compound angle AND factor formula. Please enjoy and discuss your answer :)! Edited March 22, 2017 by tutorinseoul 1 Reply Link to post Share on other sites More sharing options...
kw0573 Posted March 23, 2017 Report Share Posted March 23, 2017 I find part 2 ridiculously difficult. I gave up, but I think the logic is something like have a quadratic in sin x or cos x, then find the other root using Viete's theorem. I looked up the answer in a solver and it's not a familiar angle like pi/4 or pi/3. Thus it's also very difficult to guess and check. I graduated already but it is interesting to see if anyone in the program can figure this out! Reply Link to post Share on other sites More sharing options...
tutorinseoul Posted March 23, 2017 Author Report Share Posted March 23, 2017 21 minutes ago, kw0573 said: I find part 2 ridiculously difficult. I gave up, but I think the logic is something like have a quadratic in sin x or cos x, then find the other root using Viete's theorem. I looked up the answer in a solver and it's not a familiar angle like pi/4 or pi/3. Thus it's also very difficult to guess and check. I graduated already but it is interesting to see if anyone in the program can figure this out! Hey thanks for the reply :)!. It gets simple if you use factor formula from compound angle. Beauty of compound angle is that you can make whatever the sum of two trig equations become a product,which is nice to solve due to null factor theorem. Give it a try again :)! Reply Link to post Share on other sites More sharing options...
SC2Player Posted March 25, 2017 Report Share Posted March 25, 2017 My answer's in the attached file. Part 2 was pretty interesting; forgot about expressing something in the form rsin(x+a) until I stumbled upon it on a web page. Pretty easy tbh once you realized it - the trick is remembering this technique. Other answer.pdf 1 Reply Link to post Share on other sites More sharing options...
tutorinseoul Posted March 25, 2017 Author Report Share Posted March 25, 2017 9 minutes ago, SC2Player said: My answer's in the attached file. Part 2 was pretty interesting; forgot about expressing something in the form rsin(x+a) until I stumbled upon it on a web page. Pretty easy tbh once you realized it - the trick is remembering this technique. Other answer.pdf Very well done :)!! With this technique, we can pretty much calculate EVERY trig equation; when they come in product of two different trig, we can use null factor law to work out the x. Even if we get an equation of sum of trig, we can combine them into product of trig functions to apply null factor law again. Good job :)! 2 Reply Link to post Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.