LCD GMP 3

Which of the following functions are differentiable at x=0?
A.) sinlxl+coslxl
B.)lxl+sinlxl
C.)lxl+coslxl
D.)lcosxl+coslxl

please give the reason i know the answer! but there is a controversy between the theory and answer given!!!!!

25 Answers

1
Terminator ·

itz D.........im i rite bhaiyyaa.......????.....[1][1][1][1][1]...

1
skygirl ·

haan toh do u have anymore doubt ??

6
Aakash Sharawat ·

THE ANSWER IS D!!!!!!!!

62
Lokesh Verma ·

okie.. no worries then :)

3
msp ·

sir i have plottd in my note buk at this time i am not having my fone sir my father take it away .This is the only way dat i can draw.Tx for ur advice.

62
Lokesh Verma ·

sankara.. you dont start using a plotter because you are not good..

you dont stop studying because you dont know things before hand

Please this is for your own good.. using such plotters is suicidal.

3
msp ·

only d becos

in this option cos[x]+[cosx]=f(x)

f(0+)=cos[(0+h)]+[cos(0+h)]

f(0-)=cos[0-h]+cos[0-h]=f(0+)

and so the function is continous

and the graph for the function looks like

sry for using calc becos i am bad in drawing graph.

62
Lokesh Verma ·

@Philip ..

I have assumed h-> 0 -

1
skygirl ·

tx :)

1
Philip Calvert ·

bhaiyya i think u have given RHD and written LHD

1
Terminator ·

Bhiayya plz answer my application of Differentiation question??.......

62
Lokesh Verma ·

@sky....
LHD is given by

lim h-> 0- f(h+0) - f(0) / h

= -h - sinh /h =-2

@terminator.. yes dude.

1
skygirl ·

writing only for B...

lim h-> 0 - f(-h+0) - f(0) / -h

= -h -sinh -0 /-h =2

lim h-> 0+ f(h+0) - f(0) / h

= h + sin h - 0 / h = 2

1
skygirl ·

all of them u can c are continuous.

now jus chcek at 0+h and 0-h .

also could be done by graphs but i think by first principle its much easier.

1
skygirl ·

but i am getting B...

something 'seriously' wrong ...

39
Dr.House ·

he is priyam.

1
skygirl ·

hmm.. even function... symm abt y-axis.. so waha pe it will have y'=0...

1
skygirl ·

yeh kaun hai ??

post no 6..

62
Lokesh Verma ·

one small method to solve for such problems..

for even functions,

the RHD=0 will help

no other value of RHD at zero will give differentiable function..

why?

33
Abhishek Priyam ·

isme sochen ka kya baat hai.. its D only...

62
Lokesh Verma ·

I also think only D!

33
Abhishek Priyam ·

only D

3
iitimcomin ·

AAM I RIGHT NISH BHIYYA?????

3
iitimcomin ·

C , D

62
Lokesh Verma ·

check this one.. it is not that tough!

Your Answer

Close [X]