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anonymous
 5 years ago
Solve the following Trig equation. 33sin(theta)=cos^2(theta)
anonymous
 5 years ago
Solve the following Trig equation. 33sin(theta)=cos^2(theta)

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Rewrite cos^2 in terms of sin^2 and you have a quadratic!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so i need to solve the LHS?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0No. Use the fact cos^2x = 1  sin^2x, and then move it all to one side and solve as a quadratic

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Im not sure how to do that?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm using x as theta. 33sinx = cos^2x => 33sinx = 1sin^2x =>sin^2x  3sin  4 = 0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ahh i see how you got it now, now how do i set it up to find on all the solutions from 0<x<2pi?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Just solve it as you would the quadratic y^2  3y 4, for sin x. Note you need solutions 1 <= sin(x) <= 1 , you can ignore the others. arcsin this gives you the first solution Generally, if you find one solutions 0<x<pi you can find the other as pix , and if the solution is pi<x<0 , you have to add 2pi first before you can find them. However, in the case of this one (you'll see what I mean) it only gives one solution.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have to show my work in radians, how do i get the value to use for 2Kpi

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wut? sin^2x 3sinx  4 = (sin(x)  4)(sin(x) + 1) So sin x = ... or ... However 1 =< sin x =< 1 , so we can ignore one of these. And then use sin^1 to work out the values of x.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0My questtion says solve each of the following trignometric questions on interval 0<x<2pi, express answers for angles as exact values in radians, I've never done that type of problem like you showed me.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Is the problem that you normally work in degrees, or do you just not know how to find the angle?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i just dont know how to find the angle on this type of problem

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, OK. Well can you see what the value of sin(x) is from above?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0... I've got to go, so I'll rush this, sorry. From the factorisation, sin(x) = 1 (we can ignore sin(x) = 4 because it's too big) We use the inverse sin / arcsin / sin^1 function => arcsin(1) = pi/2 But we need a value between 0 and 2pi 20 we can add 2pi => 3/2 pi this is the only value in the inteval.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Okay thank you for your time!
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