To understand Limit in Calculus we need to learn various Laws of Limit. Limits have several different types of laws the very first law is constant law.

**Constant law: **Suppose we have f(x) =b (where f is constant for all x) then the limits as 'x' approaches 'c' must be equal to b.

: If b and c are constant: lim _{x→c} b =b

**Identity rule:** According to this law, if f(x) =x, then the limit of f as x approaches c is equal to c.

If c is a constant: lim _{x→c} x =c.

**Special law of Operational Identities:** Ø Suppose we have lim _{x→c} f(x) =L and lim _{x→c} g(x) =M and k is constant then the limit is,

**Constant multiple law:** lim _{x→c} kf(x) = k. lim _{x→c} f(x) =kL

**Addition law:** lim _{x→c} [f(x) +g(x)] = lim _{x→c} f(x) + lim _{x→c} g(x) =L+M

**Difference Law:** lim _{x→c} [f(x) -g(x)] = lim _{x→c} f(x) - lim _{x→c} g(x) =L-M

**Product Law:** lim _{x→c} [f(x)g(x)] = lim _{x→c} f(x) lim _{x→c} g(x) =LM

**Quotient law:** lim _{x→c} [f(x) /g(x)] = lim _{x→c} f(x) / lim _{x→c} g(x) =L/M (where M is not equal to zero.)

This is a brief definition of the laws of limits.