Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa

 If \mathrm{(\sin x)(\cos y)=1 / 2} then \mathrm{d}^{2} y / \mathrm{d} x^{2} at \: (\pi / 4, \pi / 4 ) equla to

Option: 1

-4


Option: 2

-2


Option: 3

-6


Option: 4

0


Answers (1)

best_answer

Solution Differentiating the given equation, we have \cos x \cos y-\sin x \sin y \mathrm{~d} y / \mathrm{d} x=0. Putting \mathrm{x=y=\pi / 4}, we have \mathrm{\left.\frac{\mathrm{d} y}{\mathrm{~d} x}\right|_{(\pi / 4 \pi / 4)}=1}. Differentiating again, we get \mathrm{-\sin x \cos y-\cos x \sin y d y / d x-\cos x \sin y d y / d x-\sin x \sin y(d y / d x)^{2}-\sin x \sin y d^{2} y / d x^{2}=0}. Putting \mathrm{x=y=\pi / 4}, we have

\mathrm{\left.\frac{\mathrm{d}^{2} y}{\mathrm{~d} x^{2}}\right|_{(\pi / 4, \pi / 4)}=-4 }.

Posted by

mansi

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

JEE Main 2026 Registration LIVE: NTA JEE form at jeemain.nta.nic.in; what's new this year?
anam-khan

JEE Main 2026: Wider gap in NIT cut-offs for home and other-state quotas; outsiders need better rank
anam-khan

JEE Mains 2026: Use of calculator 'not allowed’ says NTA; cites ‘typographical error' in information bulletin

Latest Question