Menu Close

find-coefficient-of-x-r-in-the-expension-of-2x-6y-8-




Question Number 73628 by Waseem Yaqoob last updated on 14/Nov/19
find coefficient of x^(r )  in the expension of    (2x−6y)^(−8)
findcoefficientofxrintheexpensionof(2x6y)8
Answered by mr W last updated on 14/Nov/19
(2x−6y)^(−8)   =(−6y)^(−8) (1−(x/(3y)))^(−8)   =(−6y)^(−8) Σ_(r=0) ^∞ C_7 ^(r+7) ((x/(3y)))^r   coef. of x^r :  a_r =(−6y)^(−8) ((1/(3y)))^r C_7 ^(r+7) =(C_7 ^(r+7) /(2^8 (3y)^(8+r) ))  example:  a_5 =(C_7 ^(12) /(2^8 (3y)^(13) ))=((11)/(5668704y^(13) ))
(2x6y)8=(6y)8(1x3y)8=(6y)8r=0C7r+7(x3y)rcoef.ofxr:ar=(6y)8(13y)rC7r+7=C7r+728(3y)8+rexample:a5=C71228(3y)13=115668704y13
Commented by Waseem Yaqoob last updated on 16/Nov/19
Kindly chek and give answer of q  73723+73724+73725
Kindlychekandgiveanswerofq73723+73724+73725
Commented by Waseem Yaqoob last updated on 16/Nov/19
Commented by mr W last updated on 16/Nov/19
i answer a question when i can and  when i like, automatically.
iansweraquestionwhenicanandwhenilike,automatically.

Leave a Reply

Your email address will not be published. Required fields are marked *