Solve for V in V = s^3 , if s = 4

Question

anonymous · Answer

64

anonymous · Answer

s^3 = s * s * s

anonymous · Answer

Thank you guys.

anonymous · Answer

I was wondering how he got that...

anonymous · Answer

A= 1/2 h $$ ( b _{1} + b _{2} )$$   if A = 16, h = 4, and b1 = 3

anonymous · Answer

so basically 16 = 1/2*4 (3+$$ b _{2}$$)

anonymous · Answer

I need to find b2

nowhereman · Answer

Do you know about equivalent transformation of equations?

anonymous · Answer

Uh...I'm not sure....could you please explain for me?

nowhereman · Answer

If you have a function which is injective (i.e. one-to-one) you can apply it to both sides of an equation and get an equivalent expression. i.e. the new expression is true for exactly the same allocation of the variables with values as the initial one.
So for example you can multiply with a constant (non-zero) factor on both sides, because you can invert that operation by dividing through that factor.

anonymous · Answer

okay..

anonymous · Answer

How would I use it on my problem?

nowhereman · Answer

You cant to seperate b2, but you have it enclosed in operations, so you must apply the inverses of those functions and as explained before, to get the correct b2 you have to do that on both sides.

anonymous · Answer

what would be the inverse for $$b _{2}$$?

nowhereman · Answer

You have $$16 = 2(3 + b_2)$$ given. So for a start the outermost operation on the right hand side is multiplication by 2. So first you would have to divide by 2 on both sides.

anonymous · Answer

Okay. On the first side we have 8 right?

anonymous · Answer

Square root is the inverse of the power of two.

nowhereman · Answer

There is no power of two anywhere here^^
yes, 8 is correct.

anonymous · Answer

Okay. How do I divide the second half by 2?

anonymous · Answer

Ah, I wrongly assumed $$b_2$$ was a typo of $$b^{2}$$ Sorry. :)

anonymous · Answer

s'okay!  ^^

nowhereman · Answer

First multiplying something (3+b2 e.g.) by 2 and then dividing by two again, what will you get?

anonymous · Answer

the first answer....?

nowhereman · Answer

I'm not sure what you are referring to...

anonymous · Answer

i'm confused now too

anonymous · Answer

"First multiplying something (3+b2 e.g.) by 2 and then dividing by two again, what will you get?"

nowhereman · Answer

You just have to think about that something as a number.

anonymous · Answer

okay...

anonymous · Answer

so, now what am i supposed to do? I'm confused.

nowhereman · Answer

Try to answer that last question, if you don't know it, try it out with several numbers.

anonymous · Answer

which one?

anonymous · Answer

i gotta go....
be back later