Our g of x, this g of x right there for this first case, is the x. g of x is equal to x, and f of x is equal to sine of x. Notice, we definitely know that this meets the first two constraints. The limit as x, and in this case, c is 0. The limit as x approaches 0 of sine of x is 0, and the limit as x approaches 0 of x is also equal to 0. We get our indeterminate form. Let's see at least whether this limit even exists. If we take the derivative of f of x and we put that over the derivative of g of x and take that the limit as x approaches 0 in this case, that's our c. Let's see if this limit exists.