Help!!

http://prntscr.com/1c95zm

Question

Help!!

http://prntscr.com/1c95zm

whpalmer4 · Answer

$$y + 1/y = 4$$Solve that for $y$ by multiplying both sides by $y$
$$y^2 + 1 = 4y$$Now you've got a quadratic which you should be able to solve.  Take the answers you get and plug them into the other expression and see what you get.

shubhamsrg · Answer

or, why don't you write
y^2 + 1/y^2 as y^2 + 1/y^2 + 2 - 2
see if this helps ?

anonymous · Answer

@shubhamsrg  issay se kya karun? :@

shubhamsrg · Answer

(y^2) + (1/y)^2 + 2(y)(1/y) - 2
you see an identity hidden somewhere over there? :O

anonymous · Answer

no i am not getting this :@

shubhamsrg · Answer

You understand how I expressed your given equation in this form ?
I mean everything till now is clear ?

anonymous · Answer

no :P

shubhamsrg · Answer

y^2 + 1/y^2 = (y)^2 + (1/y)^2 = (y)^2 + (1/y)^2 + 2 -2 .
You must be comfortable till here ?

anonymous · Answer

yeah!

shubhamsrg · Answer

I wrote 2 as 2(y)(1/y)

shubhamsrg · Answer

which brings us to
(y)^2 + (1/y)^2 + 2(y) (1/y) -2

anonymous · Answer

yeah...

shubhamsrg · Answer

can you tell me expansion of (y + 1/y)^2 ?

anonymous · Answer

y2+2+1/y2

shubhamsrg · Answer

yes, and what have we written above ?

anonymous · Answer

oh ok now i get this!

shubhamsrg · Answer

glad you do (Y)

whpalmer4 · Answer

so what's the answer?  prove that you get it :-)

shubhamsrg · Answer

perhaps we took a longer road, what you could have easily understood was, squaring both sides in
(y+1/y) =4

anonymous · Answer

-.- why didn't you give me this easy explanation before?

shubhamsrg · Answer

hmm, both things are same.

shubhamsrg · Answer

what? should I apologize? :P

anonymous · Answer

nah! i'll spare you :)

but could you continue your longer explanation, i mean how would it lead to the same answer?

shubhamsrg · Answer

(y+1/y)^2= 4^2
y^2 + 1/y^2 + 2 = 16

so y^2 + 1/y^2 = ...

shubhamsrg · Answer

and thanks for sparing me .-.

anonymous · Answer

(y)^2 + (1/y)^2 + 2 -2  
ye wali eq kaisay 16 answer de gi?

shubhamsrg · Answer

nahi, dono 14 denge! o.O

anonymous · Answer

kaisayy??

shubhamsrg · Answer

(y + 1/y)^2  -2 first case me =14
2nd case me to 14 hai hi clearly

anonymous · Answer

ah ok i am sorry i got this now :P

shubhamsrg · Answer

(Y)

whpalmer4 · Answer

they threw you a little curve ball with the answer choices :-)

anonymous · Answer

yeah !