MATH 105 Midterm: MATH105 Exam 3 Solutions
![MATH 105 Full Course Notes](https://new-docs-thumbs.oneclass.com/doc_thumbnails/list_view/2794081-class-notes-ca-ubc-math-105-lecture30.jpg)
91
MATH 105 Full Course Notes
Verified Note
91 documents
Document Summary
1. (a) evaluate or show that it doesn"t exist. We can use the substitution u = x2 + y, so u 12 1 = 0: (x,y) (1, 1) x2 + y lim sin(x2 + y) lim (x,y) (1, 1) sin(x2 + y) x2 + y. = lim u 0 sin(u) sin(0) u 0 d dt sin(t) (cid:12)(cid:12)(cid:12)t=0. Here we used the de nition of derivative, f(cid:48)(a) = lim x a (b) consider the area function a(x) = (cid:82) x (cid:90) 2. By the fundamental theorem of calculus, (cid:90) 2. 3 f (x) f (a) x a. 1 f (t)dt, with a(2) = 6 and a(3) = 5. f (t)dt = a(2) a(3) = 6 5 = 1 . (c) a self-employed software engineer estimates that her annual income over the next. 10 years will steadily increase according to the formula 70, 000e0. 1t, where t is the time in years.