Messages posted by Vijay Pal

hello dear

f(x)=x-1/x+1

f(ax)=(ax-1)/(ax+1)

now af(x)-ax-a/ax+a

(ax+a)afx=ax-a

ax(af(x)-1)=-a-a^2f(x)

ax=(1-af(x))/(f(x)-1/a)

now f(ax)=(1-af(x))/(f(x)-1/a)-1)/((1-af(x))/(f(x)-1/a)+1)

=(1-af(x)-f(x)+1/a)/(1-af(x)+f(x)-1/a)

=(a-a^2f(x)-af(x)+1)/(a-a^2f(x)+af(x)-1)

=(a+1)(1-af(x))/(a-1)(1-af(x))

=a+1/a-1

hence none of these is correct

hello dear yes it is posible to differentiate onto function

hello dear

halogens have only one empty orbital in thier p shell, hence can only acquire 1 negative charge, and not two

hello dear

i^i=0.20708

hello dear

it is -2e^(1/4(pi-2x)|2)

hello dear ,

no it's not true nitrogen do not have lowest ionisation enthalpy, infact it's very stable.

hello dear

net change in velocity = vf-vi=-v-(v)/t

-2v/(pi*r/v)=-2v^2/pi*r

hello dear

first we wil calculate net displacement between t=2 to t=6s

Sx=Uxt+0.5at^2

since ax=0

hence Sx(2)=80cos30*2=80*sqrt(3)

sy=80sin30*2-5*4=60

now Sx(6)=240sqrt(3)

Sy(6)=-100

delta S= 160(3)^1/2i -40j

magnitude=280

average velocity=280/4=70m/s

hello dear

the line parallel to x-2y=1 must have a slope of 1/2

hence

2(5-y)=3-x

-2y+x=-7

now intersection of this line with given line 2x+3y=14

x=1,y=4

distance = ((3-1)^2+(5-4)^2)^1/2=sqrt(5) units

hello dear

let the intensity at distance r is to be calculated

then intensity = power/area

now total surface area = 4pi*r^2

hence I=P/4pir^3

since all other things are constant for a source, only variable is r term hence,

I is inversely propotional to (distance)^2

hello dear

a unit less quantity is one which has been assigned no unit, just a number , and a dimensionless quantity is one which has a dimension of 1 in other words, with out any dimensions like mass length or time etc.

dimension less=reynolds number

hello dear

sin40*sin50+cos40cos50=0

this is the formulat for cos(a+b)

where a=40, b=50

hence the equation becomes cos(40+50)=cos90=0 , hence proved

hell dear

the value of sin(infinity) lies between -1 to 1 but it can not be determined exactlly

hello dear

V1=200v , positive

v2=200-(200/15)*5=133.33 V , positive

v3=0

V3-2=133.33v ,negative

V1-2=66.67v, positive

v1-3=200v, positive

hello dear

equation of a circle with center known is given by

(x-Xo)^2+(y-Yo)^2=r^2

(x+2)^2+(y-4)^2=r^2

now as u have not mentioned the point from where it passes, radius of circle can not be calculated if u know the point then

r^2=(Xo-x1)^2+(Yo-y1)^2

hello dear

to factorise this we need to find common term multiplied to these terms

now

x^2-y^2+yx^2-xy^2=(x+y)(x-y)+xy(x-y)=(x-y)(x+y+xy)

hello dear

potential difference is the energy difference per unit entity. between two points.

hello dear

covalency is 4 as there are 4 electrons shared between O and N atoms

hello dear 4th is wrong

hello dear

mole is a unit that is used to express quantity /number of same entity

1mole = 6.023*10^23 atom/molecules

usually we use moles of atoms or molecules to calculate the amount of substance required in a reaction.

for example

a+2B--> 3C +4D

then it means

1 mole of a reacts with 2 mole of b to give 3 moles of c and 4 moles of d

1 mole of a substance has same weight numerically as in amu units, but in grams. for example

molecular mass of O2=32 amu

and molar mass of O2=32g

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