SOLUTION: (3/5 cube root of -125)-(1/4 cube root of 56)+(1/2 cube root of 189) needs to be simplify. Help.

Algebra ->  Square-cubic-other-roots -> SOLUTION: (3/5 cube root of -125)-(1/4 cube root of 56)+(1/2 cube root of 189) needs to be simplify. Help.      Log On


   

Question 540529: (3/5 cube root of -125)-(1/4 cube root of 56)+(1/2 cube root of 189) needs to be simplify. Help.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Note that +root%283%2C-125%29+=+-5+
and
+189+=+7%2A27+
+189+=+7%2A3%5E3+
so
+root%283%2C189%29+=+3%2Aroot%283%2C7%29+
also,
+56+=+7%2A8+
+56+=+7%2A2%5E3+
+root%283%2C56%29+=+2%2Aroot%283%2C7%29+
Now the problem becomes

+-3+-+%281%2F2%29%2Aroot%283%2C7%29+%2B+%283%2F2%29%2Aroot%283%2C7%29+
+-3+%2B+%28+root%283%2C7%29%2F2+%29%2A%28+3+-+1+%29+
+-3+%2B+root%283%2C7%29+