 In this video, we provide the solution to question we're 17 from the practice final exam for math 1210. We're given the function g of x equals sign of x and we're asked to find the equation for the tangent line of this function at x equals pi halves. We need to write that in slope intercept form. Now this question, if you've been following along with this series, with this course, might be familiar to you. This is a practice question we saw on exam number two. The difference now, of course, is that in exam number two, you were given the derivative for the final exam, we're expected to compute it, which isn't so bad for us. We know that the derivative of g here is gonna be cosine, the derivative of sine is equal to cosine. Then from here, the rest of the problem is gonna be very, very similar, right? The equation of the tangent line will look like y minus, minus g of a is equal to g prime of a times x minus a, where a here is the point of tangency. This is given as pi halves right here. So plug them into our formula, we get y minus g of a, so that's gonna be sine of pi halves. This is gonna equal the derivative, which was cosine evaluated at pi halves, the point of tangency, and then we times that by x minus the a value pi halves. So sine of pi halves is equal to one. Cosine at pi halves is actually equal to zero. And so this would simplify just to be y minus one is equal to zero, or in other words, y equals one. So it turns out that the tangent line is actually horizontal at this location. So we get as our equation y equals one.