TMH Q

Δ=
1+x (1+x)a (1+x)bc

1+x (1+x)b (1+x)ca

1+x (1+x)c (1+x)ab

find coeff. of x and x2.

7 Answers

62
Lokesh Verma ·

(1+x)\left\{(1+x)^{b^2a}-(1+x)^{c^2a}+(1+x)^{c^2b}-(1+x)^{a^2b}+(1+x)^{a^2c}-(1+x)^{b^2c}\right\}=x\left\{(1+x)^{b^2a}-(1+x)^{c^2a}+(1+x)^{c^2b}-(1+x)^{a^2b}+(1+x)^{a^2c}-(1+x)^{b^2c}\right\}+\left\{(1+x)^{b^2a}-(1+x)^{c^2a}+(1+x)^{c^2b}-(1+x)^{a^2b}+(1+x)^{a^2c}-(1+x)^{b^2c}\right\}

There should be a simpler method.. but right now i cant think of any! :(

11
Gone.. ·

ne 1 ...easier way??

1
Arshad ~Died~ ·

take (1+x)^abc common from the third row
u get
Δ=
1+x (1+x)^a (1+x)^1/a

1+x (1+x)^b (1+x)^1/b

1+x (1+x)^c (1+x)^1/c
now put 1+x=t
and solve

1
$ourav @@@ -- WILL Never give ·

according to arshad,i hav reached to

=> t^abc [ t^ab-bc-a2+2ac - t^ac-bc-a2+2ab ]

can ne1 help me after dis???

62
Lokesh Verma ·

after my 2nd post..

coeff of x seems to be obvious?

b2a+c2b+a2c-a2b-b2c-c2a
=(a-b)(b-c)(c-a)

and for x^2 it will be

seems to be a bit more clumsy.. :(

1
$ourav @@@ -- WILL Never give ·

but sir,for me coefficient of x^2 is coming to d answer u got in coefficient of x........

62
Lokesh Verma ·

damn.. i have kept this one posted as teh most stupid wrong answer and no one ever saw what i did :( :( :(

There is a stupid stupid stupid mistake in what i have done :D

let me rewrite it...

(1+x)\left\{(1+x)^{b+ba}-(1+x)^{c+ca}+(1+x)^{c+cb}-(1+x)^{a+ab}+(1+x)^{a+ac}-(1+x)^{b+bc}\right\}

Now can you guys solve it?

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