Question

1. Expand (1-2x)⁶ up to term in x³ 
2. Use the expansion above to evaluate (1.02)⁶ correct to 4 decimal places.

Answer 1

1. 1+ 6(2x)¹ + 15 (2x)² + 20(2x)³
   1+12x + 60x² +160 x³
    
2. 1-2x = 0.98
   -2x=0.98-1=-0.02
   or 1-0.98=2x
   2x=0.02
   x=0.01 
   1+12(0.01 ) + 60(0.01)²+160 (0.01)³
   1+ 0.12+0.006 + 0.00016
   =1.1262(4 d.p)