Bionomial thm

(x-1/x)^10(x+1/x)^4= { [(x - 1/x)(1 + 1/x)]^4 } (x - 1/x)^6= [(x^2 - 1/x^2)^4] (x - 1/x)^6= (x^8 - 4(x^6)/x^2 + 6(x^4)/x^4 - 4(x^2)/x^6 + 1/x^8) *
(x^6 - 6(x^5)/x + 15(x^4)/x^2 - 20(x^3)/x^3 + 15(x^2)/x^4 - 6x/x^5 + 1/x^6)= (x^8 - 4x^4 + 6 - 4/x^4 + 1/x^8) (x^6 - 6x^4 + 15x^2 - 20 + 15/x^2 - 6/x^4 + 1/x^6)constant term = (- 4)(- 6) + 6(-20) + (- 4)(- 6)= - 72