I can't see where I'm going wrong here:
A rubber ball is dropped from a height of 6m. It falls vertically before hitting the ground and bouncing straight back up. After the first time it hits the ground, it ascends to a height of 5.52m. The maximan height that the ball reaches after each bounce form a geometric sequence.
Show algebraically that the first time the ball bounces to a maximan height of less than one metre is after the 22nd bounce. The first time I attempted this I did this:
Un = a(r^n)
a=6
r=0.92
n=number of bounces
1> 6 x 0.92^n
1/6 > 0.92^n
then I took log base 0.92 of both sides but this gave
21.49>n
I managed to get the the answer another way but I just wondered why my original method wasn't working?