Messages posted by flowers_rsss

ohh we have to take2 cases
aditi is correct!!

is the answer -2<=x<=2 ??

$\int \pi/2 - 2{cos}^{-1}\sqrt{x}/\pi/2$

$\int 1 - 4/\pi {cos}^{-1}\sqrt{x}$

$= x-4/\pi \int 2y{cos}^{-1}y where y =\sqrt{x}$

applying integration by parts we get

$x-8/\pi [ytany-log secy ]$ where y =root over x

correct if i am wrong!!

$\int \frac{1}{secx+cosecx}=\int \frac{sinxcosx}{sinx+cosx}=\int\frac{sin2x}{2(sinx+cosx)}$

$\int \frac{(sinx+cosx)^2-sin^2x-cos^2x}{2(sinx+cosx)}$

$= \int [(sinx+cosx)- \frac{1}{sinx+cosx}] *\frac{1}{2}$

= $\frac{1}{2} (sinx-cosx-1/\sqrt{2} log tan (x/2+\pi/8 ) )$

correct if iam wrong!

**** hey i forgot to write dx in its place jst see it

The structural features which influences the chemical reactions due to bulky substituents is known as stearic effect. When the bulkier groups hinder the reaction it is called stearic hindrance wich may be due to 1) the sheer bulk of the substituents causing the approach of the reagent more difficult or may be due to 2) electronic factor i e., promoting or inhabiting the electron availabilityat a particular site!! eg:- carboxylic groups with highly substituted alpha carbon are esterified with difficulty due to steric effect.

hey this is another method:

since here discriminant is greater than zero and x^2 coeff is less than zero

use the method

I = [1/root(-a )*{ sin^-1 (-d/dx (lx^2+mx+n)/root over discriminant]}

where l=-1

m=(a+b)

n=-ab

Re:solvethe given eqn can be written as

$\int$ cosx / (sinxcosx+1) dx

= $\int$ 2cosx/ sin2x+2 dx

= $\int$ cosx+sinx / 2+sin2x dx + $\int$ cosx-sinx/ 2+sin2x dx

let that be equal to ${I}_{1} +{I}_{2}$

for ${I}_{1}$ put sinx-cosx= t ............................(1)

(sinx+cosx)dx=dt

squaring (1)

1-sin2x=t^2

sin2x=1-t^2

similarly for ${I}_{2}$ take sinx+cosx= p and proceed

finally by solving we get

dt/3-t^2 +dt/1+t^2

=1/2 $\sqrt{3}$ log[root3+2/ root3-2] +tan^-1 (p)

where t=sinx-cosx and p=sinx+cosx

correct if i am wrong!!

the ans is given as only reflexive!1

yup i posted this qn to know that!!

pls any one do explain the properties!

Let S be the set of integers .For a,bS , relation R is defined by aRb iff |a-b|<1 then R is

1)only reflexive

2)only symmetric

3)only transitive

4)equivalence

pls explain!!

USE THE FORMULA

VELOCITY OF SOUND IN AIR

= ROOT OVER [(GAMMA * PRESSURE) / DENSITY}

WHERE GAMMA = MOLAR SPECIFIC HEAT CAPACITY

AND

GAMMA = 1+2/f

where f is degree of freedom

hey in news they said that they are going to release key tommorrow!!

In physics and chemistry you have to learn concepts in depth which are missing in our state syllabus.
And in Mathematics we complete 25% extra than in iit jee syllabus
just practice more typical questions and complete deepthi series atleast twice, thats a wonderful book!!

REMEMBER PHYSICS AND CHEMISTRY U HAVE TO DO A LOT MORE !!!!!

chennai superkings

hey see this

given a+b+c=0

therefore

substituting in given exprssn

ax^2+bx+(-a-b)

=a(x^2-1)+b(x-1)=0

taking( x-1) common

(x-1)(ax+a+b)=0

that implies

x=1 or ax=-(a+b )

=ax=c (given a+b+c=0)

therefore x=c/a

therfore answer is 1, c/a

correct if i am wrong!!

Uday is exactly correct
answer is C

expanding 1+tanx/1-tanx

we get

cosx+sinx/cosx-sinx

d/dx of cosx -sinx is -(sinx+cosx)

so let

cosx-sinx=t

then we get

$\int$ -dt/t

= -logt

=-log(cosx-sinx)

correct if i am wrong!!!

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