Question

The product of 2 x 104 cm and 4 x 10–12 cm, expressed in scientific notation is ____.

Answer 1

Answer:    8 * 10⁻⁸  cm²  .
______________________________________________________
Explanation:
______________________________________________

(2 * 10⁴ cm) * (4 * 10⁻¹² cm)  =

2 *4 * 10⁴ * 10⁻¹² = 8 * 10⁽⁴⁺⁽⁻¹²⁾⁾ =  8 * 10⁻⁸  cm² .
_________________________________________

Note the follow property of exponents:
_____________________________________________________
 
xᵃ * xᵇ = x⁽ᵃ ⁺ ᵇ⁾  ;  as such:  " 10⁴ * 10⁻¹² = 10⁽⁴⁺⁽⁻¹²⁾⁾ = 10⁻⁸ " .
_____________________________________________________