use the command \cdot to put the multiplication dot in... you can't post images in LaTeX and expect them to work.
do one piece at a time.
um. so like, you have 3b^3, and multiply it by 1b? so it's... still 3b^3? or did i mess up somewhere?
so we have
work out the cubed part first, we get:
now multiply the b's, using the first rule you posted
now try the others