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hey sp the question is not clear, do write it again

hey ask him to chill out, nothing happens thr, the chance of rejection is far toooooooooo less, so ask him jst to 4get it, n study well.... nothing will happen

let cosec x = t

then -cosec x cot x dx = dt

=> cosec x dx = -dt/ [sqrrt(t² -1)]

thrfore

_{[ ]}

^{[ ]} cosec ³ x = _{[ ]}

^{[ ]} - t²/ [sqrrt(t² -1)] dt

subtracting and adding 1 in numerator we have,

RHS =

_{[ ]}

^{[ ]} -[sqrrt(t² -1)] dt - _{[ ]}

^{[ ]} [1/{sqrrt(t² -1)}] dt

and for this we hav standard formulae.....

if any problem, do ask again

well dnt knw if 250 is gud enuf or not, but yeah papers are normally as shakir said, except this tym, cuz maths paper was a bit easy this tym, for a change.... otherwies, the paper almost bounces back in the 1st sight!!!! physics is okayish, n chem is easy, providede its not wrong!!!!

shakir r u giving the aits????

Tautomerism refers to an equilibrium between two different structure of the same compound. Usually the tautomers differ in the point of attachment of a hydrogen atom. One of the most common examples of a tautomeric system is the equilibrium between a ketone and its enol form,

where K_e is the equilibrium constant. For ordinary ketones K_e is usually very small, but in

-dicarbonyls the possibility of intramolecular H-bonding can make enol formation much more favorable.

The value of K_e depends greatly on the identity of the two groups R and R'.

Solvent polarity is also very important in determining the magnitude of K_e. The enol form is less polar than the keto tautomer because of the intramolecular hydrogen bonding. Thus, an increase in solvent polarity favors the more polar keto form.

hopefully this would hav helped u a bit atleast!!!

he he, even m no gud at it, n thats y i lost in even aieee last yr, its too much of mugging, esp the inorganic part, n biomolecules chapters, u knw shakir, i hav left all those last chapters in board even, jst had read about carbohydrates a li'l(watevr is in jee syllabus).... n the rest evrything has left on god's name

... i think dnt give them much thought, i repeat not MUCH thought....

hey me too, m also studying on my own, waise hav done two yrs course at fiitjee, along 11th and 12th, n found it really helpful !!!!

hey shakir, u r a real genius i mst say.... hats of to u too man!!!

Its used because, as soon as banzaldehyde is formed, it reacts with acetic anhydride to form benzyldiene acetate and thus further oxidation of benzaldehyde to benzoic acid is checked by acetic anhydride

C₆H₅CH₃+ CrO₃ ---------> C₆H₅ CHO <====> C₆H₅CH(OCOCH₃)₂

where <===> implies reversible rxn....

well vinu is absolutely correct, as always

....and the scond one can be done by partial fraction method...

yeah madhuri is absolutely right, its not the resonance factor but the deactivation of ring due to the lewis acid behaviour of aluminium chloride

yeah D has also to be a perfect square, n a has exactly 32 values, as given in the answer, i dnt knw how they r getting it???

thanx madhuri

hey prakhar, may i knw ur percentiles in aits, ofcourse if u dnt mind!!

hey, thanx for the salute, for this also, n others too.... n keep saluting

I hav 3 vowels in my name, so u r right, for the next, he/she will be having name started with 's'