Let the function P be defined by P(x) = x3 + 7x2 – 26x - 72 where (c + 9) is a factor. To rewrite the function as the product of two factors, long division was used but
an error was made:
22 + 162 +118
2 +973 + 722
+ 7x2 – 262 – 72
-23 +922
1612 - 262
-16x2 + 144x
118x - 72
-118x + 1062
990
How can we tell by looking at the remainder that an error was made somewhere?