x varies directly as the product of u and v and inversely as their sum.If x=3 when u=3 and v=1.

x = kuv/(u+v)

when you come up with a question, this should help answer it.

To understand how x varies with u and v, let's break down the information given:

1. x varies directly as the product of u and v: This means that x is directly proportional to the product of u and v. In other words, if we increase the value of u or v, x will increase proportionally.

2. x varies inversely as their sum: This means that x is inversely proportional to the sum of u and v. In other words, if we increase the value of u or v, x will decrease proportionally.

Now, let's use this information to find the value of x when u=3 and v=1.

Since x varies directly as the product of u and v and inversely as their sum, we can express this relationship mathematically as:

x = k * (u * v) / (u + v)

where k is a constant of proportionality.

Using the given values, we can substitute u=3 and v=1 into the equation:

3 = k * (3 * 1) / (3 + 1)

Simplifying the equation further, we get:

3 = k * 3 / 4

Now, we can solve for the constant k:

k = (3 * 4) / 3

k = 4

So, the constant of proportionality is 4.

Now, substituting this value of k back into the equation, we can find the value of x:

x = 4 * (3 * 1) / (3 + 1)

Simplifying the equation further, we get:

x = 4 * 3 / 4

x = 3

Therefore, when u=3 and v=1, the value of x is 3.