The coefficient of y∧15×∧2 in expansion of (y∧3+x)∧7 is (15×2)+(3×7)= 51
To calculate the speed, divide 15.75 by 2.25 and you get 7 mph.
To find the greatest possible product, you need the greatest possible numbers. The largest possible 2-digit number is 99. The largest possible 1-digit number is 9. Therefore, 99 * 9 will be the largest possible product under these circumstances.
99 * 9 = 891
Hope this helps! :)
