Rewrite (8-9x)^(2/3) as (8(1-(9/8)x)^(2/3)=4(1-(9/8)x)^(2/3). Now apply the C4 binomial formula in the formula booklet, so: 4(1 - ((9/8)x)^(2/3)= 4[ 1 + (2/3)*((-9/8)x) + (2/3)((-9/8)x)^2 .....]= 4[ 1 - (3/4)x + (27/32)x^2 ....]=4 - 3x + (27/8)x^2.... so the first 3 terms are 4 - 3x + (27/8)x^2