Answer
$$32x^{15}-240x^{12}y+720x^9y^2-1080x^6y^3+810x^3y^4-243y^5$$
Work Step by Step
We know from the Binomial Theorem (page 693) that we can expand the given expression without multiplying it out. Doing this, we obtain:
$$32x^{15}-240x^{12}y+720x^9y^2-1080x^6y^3+810x^3y^4-243y^5$$