+0  
 
+3
264
3
avatar

if pi/2 < x < pi and sinx = 2/5 then tanx = ؟

Guest Jul 27, 2014

Best Answer 

 #2
avatar+91471 
+11

I always draw the right angled triangle for these.  

x is one of the acute angles

2 is the opposite side, 5 is the hypotenuse.

Get the other side using pythagoras' Theorum

then read tanx of the triangle.

plus as Alan said it is in the second quad so it is negative. 

Melody  Jul 27, 2014
Sort: 

3+0 Answers

 #1
avatar+26406 
+8

This is in the second quadrant where tan is negative, so tanx = -2/√(52-22) = -2/√21

Alan  Jul 27, 2014
 #2
avatar+91471 
+11
Best Answer

I always draw the right angled triangle for these.  

x is one of the acute angles

2 is the opposite side, 5 is the hypotenuse.

Get the other side using pythagoras' Theorum

then read tanx of the triangle.

plus as Alan said it is in the second quad so it is negative. 

Melody  Jul 27, 2014
 #3
avatar+1828 
+3

thanx for all 

xvxvxv  Jul 27, 2014

20 Online Users

avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details