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# learn trigonometric ratios of allied angles

Question:How do I find the 6 trigonometric ratios(sin, cos, tan, csc, sec, cot) for both a triangle where one of the sides is a square root, and where all Im given is an angle (120 degrees for example). help please??

Answers:You can not define a triangle by one angle and one side ! That does not determine an unique triangle. If you want the values for 120 , learn the unit circle ! sin 120 = ( 3)/2 cos 120 = - 1/2 tan 120 = - 3 csc 120 = (2 3)/3 sec 120 = - 2 cot 120 = - ( 3)/3 QED

Question:I was looking through the sample problems in my textbook and I don't understand why cos pi/6 becomes sqrt 3/2. The sample problem was done like this: cos pi/6 = x/50 sqrt 3/2 = x/50 50 squrt 3 / 2 = x x = 25 sqrt 3 Can someone please explain to me why cos pi/6 turned into sqrt 3/2?

Answers:Cos pi/6 becomes sqrt(3)/2 when you use it on a unit circle. This will help: http://en.wikipedia.org/wiki/Unit_circle The unit circle's hypotenuse is always 1 [drawing the circle], and like you said in the question we use it for ratios in triangles.

Question:Determine the exact value of this trigonometric ratio: 11pi / 6 Answer: 3 / 3 Please show your steps working towards the answer, additionally do not use a calculator in any of your steps, your help is much appreciated. ...The answer is not 2, I gave the answer in my question. I meant tan of my mistake.

Answers:Hi, Tan(11pi/6) converting the angle from radians into degrees => Tan(11*180/6) => Tan(330) => - 3 / 3 so the answer is negative 3 / 3 not 3 / 3. Hope I helped.

Question:Hey. I know what sin, con, and tan are. I'm just having trouble with one set of problems. Here's what the directions on the worksheet say: Let angle A be an acute angle in a right triangle. Approximate the measure of angle A to the nearest tenth of a degree. 1. sin A= 0.16 2. tan A= 8.4 3. cos A= 0.81 There are no pictures or diagrams. My guess is that I plug in the numbers in my calculator for cos-1, sin-1, and tan-1, but I'm not sure. Please explain atleast one of the problems from above so I can do the rest of my worksheet correctly. Thanks : ) Thanks.

Answers:You're right. Just do the inverse of each function. So for A, you would do sin-1 0.16 and get an answer.