badge image

Enroll For Free Now & Improve Your Performance.

×
User Icon
User Icon
User Icon
User Icon
User Icon

Thank you for registering.

One of our academic counsellors will contact you within 1 working day.

Please check your email for login details.
MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
Grade: 12

                        

Q.26 answer for 2 nd or question alone, answer as soon as possible.

8 months ago

Answers : (2)

Aditya Gupta
2069 Points
							
call theta= a
x= e^a(2cosa+cos2a) so that dx/da= e^a(2cosa+cos2a – 2sina – 2sin2a)
y= e^a(2sina+sin2a) so that dy/da= e^a(2sina+sin2a+2cosa+2cos2a)
now, by chain rule dy/dx= [dy/da]/[dx/da]
= e^a(2sina+sin2a+2cosa+2cos2a)/e^a(2cosa+cos2a – 2sina – 2sin2a)
= (2sina+sin2a+2cosa+2cos2a)/(2cosa+cos2a – 2sina – 2sin2a), which is clearly not equal to tan(pi/4+3a/2), as can be seen by putting a= 0, whence (2sina+sin2a+2cosa+2cos2a)/(2cosa+cos2a – 2sina – 2sin2a)= 4/3 but tan(pi/4+3a/2)= 1.
hence question is certainly WRONG, as can also be verified on wolfram alpha ‘paramteric derivative calculator’
KINDLY APPROVE :))
8 months ago
Arun
25285 Points
							
I have assumed theta as a for the sake of writing
 
dy/da = e^a ( 2 sin a + sin2a) + e^a ( 2 cos a + 2 cos2a)
 
dx/da = e^a ( 2 cosa + cos2a) - e^a ( 2 sin a - 2 sin2a)
 
Hence 
dy/dx = (sina + sin2a + cos a + cos2a) /(cosa + cos2a - sina - sin2a)
 
 = [2 sin (3a/2) cos (a/2) + 2 cos (3a/2) cos (a/2)] / [ 2 cos(3a/2) cos (a/2) - 2 sin (3a/2) cos (a/2)]
 
 = [ sin (3a/2) + cos(3a/2) ]/ [ cos(3a/2) - sin (3a/2)]
 
 =[ 1 + tan (3a/2) ]/ [1 - tan (3a/2)]
 
 = tan (π/4 + 3a/2)
 
Hope it helps
 
Thanks and regards
Arun
8 months ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution


Course Features

  • 51 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions


Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details