We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
0
653
1
avatar+559 

The angle θ lies in Quadrant  II .

sinθ=34

What is cosθ ?

 Feb 21, 2018

Best Answer 

 #1
avatar+7354 
+2

sin2θ  +  cos2θ   =   1

 

(3/4)2  +  cos2θ   =   1

 

cos2θ   =   1 - (3/4)2

 

cos2θ   =   1 - 9/16

 

cos2θ   =   7/16

 

cos θ   =   ±√[ 7/16 ]

 

cos θ   =   ±√7 / 4

 

Since  θ  is in Quadrant II , cos θ is negative.

 

cos θ   =   - √7 / 4

 Feb 21, 2018
 #1
avatar+7354 
+2
Best Answer

sin2θ  +  cos2θ   =   1

 

(3/4)2  +  cos2θ   =   1

 

cos2θ   =   1 - (3/4)2

 

cos2θ   =   1 - 9/16

 

cos2θ   =   7/16

 

cos θ   =   ±√[ 7/16 ]

 

cos θ   =   ±√7 / 4

 

Since  θ  is in Quadrant II , cos θ is negative.

 

cos θ   =   - √7 / 4

hectictar Feb 21, 2018

24 Online Users

avatar
avatar
avatar