SOLUTION: SHOW THAT: A) TOTAL SURFACE OF A CUBE TWICE THE SQUARE OF ITS DIAGONAL. B) VOLUME OF A CUBE IS 1/9 TIMES SQUAROOT OF 3 TIMES THE CUBE OF ITS DIAGONAL. THANK YOU....

Algebra ->  Surface-area -> SOLUTION: SHOW THAT: A) TOTAL SURFACE OF A CUBE TWICE THE SQUARE OF ITS DIAGONAL. B) VOLUME OF A CUBE IS 1/9 TIMES SQUAROOT OF 3 TIMES THE CUBE OF ITS DIAGONAL. THANK YOU....       Log On


   



Question 404190: SHOW THAT:
A) TOTAL SURFACE OF A CUBE TWICE THE SQUARE OF ITS DIAGONAL.
B) VOLUME OF A CUBE IS 1/9 TIMES SQUAROOT OF 3 TIMES THE CUBE OF ITS DIAGONAL.

THANK YOU.... PLS. HELP ME...

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
a) Let s = side of a cube. Then d+=+sqrt%28s%5E2+%2B+s%5E2+%2Bs%5E2%29+=+sqrt%283s%5E2%29+=+sqrt%283%29%2As, or s++=d%2Fsqrt%283%29.
==> TSA+=++6%2As%5E2+=+6%2A%28d%5E2%2F3%29+=+2d%5E2

b)