What identity is this? (Division to multiplication )

AI Thread Summary
The discussion centers on the identities related to the transformation of division into multiplication. It clarifies that there is no direct identity that converts a/b to ab or A^2/B^2 to (A^2)(B^2). Instead, it highlights that dividing by b can be expressed as multiplying by its reciprocal, 1/b. Additionally, it mentions the Newton-Raphson method for approximating division through iterative multiplication and addition. Ultimately, the inquiry confirms that such transformations are not standard identities.
musiclover55
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This isn't a homework help issue, I just want to know what identity(?) this is.

a/b to ab

or A^2/B^2 to (A^2)(B^2)
 
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musiclover55 said:
This isn't a homework help issue, I just want to know what identity(?) this is.

a/b to ab

or A^2/B^2 to (A^2)(B^2)
There is no identity that converts a/b to ab, nor is there one to convert A2/B2 to A2B2.

What you might be thinking of is this one:

$$ \frac{a}{b} = a \cdot \frac{1}{b}$$

In other words, dividing by a number b is the same as multiplying by the reciprocal of b (1/b).
 
Mark44 said:
What you might be thinking of is this one:

$$ \frac{a}{b} = a \cdot \frac{1}{b}$$

Or maybe this one:$$
\frac a {\frac 1 b} = ab$$
 
Although this probably isn't what you're looking for, there is a way to implement division or more specifically 1/b by iterating multiplications and additions via Newton Raphson method, but this seems unlikely to be what you're looking for.

For 1/b the iternation is:

xi+1 = xi (2 - b xi)

This converges quadratically. For integers, usually a table of bytes is used to get the initial approximation.
 
Yea, thanks everyone. I thought that was possible, but obviously it's not lol.
 
Yet another possibility: A/B= AB-1
 
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