Use Binomial Theorem simply ,
So rth term in the given binomial expansion will be :
(-1)r . nCr (x2)n-r (1/x)r ; here n = 100
==> (-1)r . nCr x200 - 3r = x198
But equating 200 - 3r and 198 we get r = 2 / 3 which is not an integral value..
But we require that r be an integer as it is used in binomial coefficient nCr..
Hence there is no term containing x198..
So coefficient of x198 in the given binomial expansion = 0
of they had asked for x197 then coefficent is there right?because it is of the form 22 -3r.
so what would have been the answer?
100 C 1 ??
i know 100c99 and 100c1 are same things but by formula we get 100c1..right?
but by the equation,we are getting 100c1 .right??
or is it - (100c1) because of (-1) r. ..??
can you confirmthe coefficent of x197 ??is it (- 1)(100c1)?