Let g_1, g_2, g_3, be a geometric sequence. If g_{23} = 16 and g_{28} = 24, what is g_{43}?
The formula for a geometric sequence is an=a1rn−1, where a1 is the first term, r is the common ratio, and n is the term number.
We know that g23=16 and g28=24. We can use these values to find the common ratio r.
g28 = g23 r^{28 - 23} 24 = 16r^5 r^5 = 2 r = 2^(1/5)
Now that we know the common ratio, we can find g43.
g43=g23r^{43-23} g43 = 16*(2^{1/5})^(43-23) g43 = 16*(2^(1/5))^20 g43 = 16*2^4 g43 = 128
Therefore, g43=128.