Will give medal and fan!
Given tan theta=-sqrt2/2 and theta lies in quadrant IV, find cos theta/2
@SyedMohammed98 @TheSmartOne
@mady111
yes!
You can help me?
i can
Sweet. What do I need to do first?
hold on
\[\sin \theta \sqrt{2/2}\]
\[\cos \theta=-\sqrt{2/2}\]
- in the first on to
\[\tan \theta=1 \cot=1 \csc -\sqrt{2} \sec =-\sqrt{2}\]
since the angle formed in quadrant III is 90 degrees, then if we bisect that angle we'll get half of that which is 45 degrees.... so we know that in a right triangle with 45 degrees, the sides will have a ratio of 1:1:square root of 2 so let's suppose our hypotenuse is sqrt of 2 and the legs have measure of 1. Since we're in quadrant 3 both legs will have measure of -, (because at quadrant 3, x and y are both negative) 1 but the hypotenuse will still be sqrt2... so we'll have using this info, you can now compute for the 6 trig. functions of theta.. so sin theta=-1/sqrt2=-sqrt(2)/2 cos theta=-1/sqrt2=-sqrt(2)/2 tan theta=sin theta/cos theta <a trigonometric identity since sin theta=cos theta in this case, tan theta=1 cot theta=1/tan theta=1/1=1 sec theta= 1/cos theta=1/(-1/sqrt2)=-sqrt2 csc theta=1/sin theta=1/(-1/sqrt2)=-sqrt2
So I use cos theta=-1/sqrt2=-sqrt(2)/2
yes you got it
Do I have to plug in anything for tan?
Or I just put that equation in the calculator?
no put that in the calculator
did you get the answer you was looking for
I put it into wolfram because I don't have a graphing calculator and the answer was exactly what I put in
hmm ill do it a different way for you
Alright
The six trig functions are listed below @ stands for theta. x,y, and r are in reference to the trig functions related to a unit circle. Cos@ = adj/hyp or x/r....Sec@ = hyp/adj or r/x Sin@ = opp/hyp.or y/r..Csc@ = hyp/opp or r/y Tan@ = opp/adj or y/x...Cot@ = adj/opp or x/y Since your angle is QIV, Xs are positive, Ys are negative This means that your Sine, Cosecant, Tangent, and Cotangent are going to be negative. With that said... The sec@ = Sqrt(3)/1 remember any number can be written as a ratio by putting it over a 1. This is the key. x = 1 and r = sqrt(3). Using the Pythagorean theorem since we form a right triangle in drawing the coordinate system and @ in the 4th Quad, we get...that x = 1, r = sqrt(3) and y is all we need to find. (1)^2 + y^2 = (sqrt3)^2 y = sqrt(2) Now you have adj or x = 1, opp or y = sqrt(2), and hyp or r = sqrt(3) Write your functions and remember which ones are negative. Sin@ = y/r = sqrt2/sqrt3 = sqrt6/3 (negative) Cos@ = x/r = 1/sqrt3 = sqrt3/3 (positive) Tan@ = sqrt2/1 = sqrt 2 (negative) Csc@ = r/y = sqrt3/sqrt2 = sqrt6/2 (negative) Cot@ = x/y = 1/sqrt2 = sqrt2/2 (negative
is this any better?
I'm sorry. I'm still confused. I'm not sure what to do next.
okay ill draw it out for you
Okay thank you
|dw:1430167828760:dw|
Join our real-time social learning platform and learn together with your friends!