Find the first 3 terms in the expansion of (2+3x)^5 in ascending powers of x

Answer 1

(2+3x)^5

= 2^5 + 5(2^4)(3x) + 5C3(2^3)(3x)^2 + ...

= 32 + 5(16)(3x) +5!/3!2!(8)(9x^2)

=32 + 80(3x) + [(5)(4)(3)(2)/3(2)(2)]72x^2

= 32 + 240x + 720x^2 + ...