Most students, from grade 7 on, are familiar with the order of operations BEDMAS (first brackets, then exponents, then division, next multiplication, then addition, finally subtraction). However, sometimes the order gets mistaken.<\/p>\n
Example 1<\/strong>: Simplify -(-2)^4<\/p>\n Solution:<\/strong><\/p>\n The correct way to proceed is to evaluate the exponent (-2)^4 first, which gives 16. Next, multiply it by the negative in the lead, arriving at -16. The correct answer is -16.<\/p>\n The mistake often made is “cancelling” the two negatives by mulitplying them together first. That can’t be done, since it means multiplying before evaluating the exponent.<\/p>\n Example 2<\/strong>: Simplify 2(3)^2<\/p>\n Solution:<\/strong><\/p>\n The correct way to proceed is to evaluate the exponent (3)^2 first, which gives 9. Next, multiply it by the 2 in front, arriving at 18. The correct answer is 18.<\/p>\n The mistake often made is to multiply before evaluating the exponent, as follows:<\/p>\n 2(3)^2=6^2=36 (wrong)<\/p>\n While this mistake might seem obvious, it leads to many lost marks. Sometimes a flaw only becomes obvious after someone points it out (likely because someone pointed it out to them earlier).<\/p>\n HTH:)<\/p>\n