Question

Find the constant term or the term independent of x in the expansion of (3x – 5/x to the 2nd power )and to the 9th power

Answer 1

(3x - 5/x)^2 = 9x^2 -30 + 25/x^2

The constant term is -30.

Do the multiplication by (3x - 5/x) eight more times for the second part of your question.

Answer 2

In the expansion of (3x - 5/x)^n
there is no term independent of x, (a constant term), if n is odd, in your case 9

the general term would be C(9,r)(3x)^r(-5/x)^9-r
=C(9,r)(3)^r (-5)^^-rx^r-9
=C(9,r)(3)^r(-5)^9-rx^2r-9

so 2r-9 = 0 for the x to drop out
but r has to be a whole number, so there is no solution

Answer 3

Where did you get -30 from?

to drwls

Answer 4

thz i am done wit this