Try another version of this question Get help: Box 1: Enter your answer as a number (like 5, -3, 2.2172) or as a calculation (like 5/3, 2^3, 5+4)
Simplify:
`4 sqrt(21) * 3 sqrt(42)`
(entry tip: to type type "5sqrt(3x)" - no quotes)
Enter DNE for Does Not Exist, oo for Infinity `252 sqrt(2)`