Specialist Exam 1 Solutions

[Escobar]

Here's some more comforting proof

"To describe the complex numbers, we use a formal symbol i representing √−1; then a complex number is an expression of the form
(2) a + bi, a, b real numbers.
If a = 0 or b = 0, they are omitted (unless both are 0); thus we write
a + 0i = a, 0 + bi = bi, 0 + 0i = 0 ."

from http://math.mit.edu/~jorloff/suppnotes/suppnotes03/c.pdf

thanks hopefully i get full marks then

[Splash-Tackle-Flail]

For the tan graph question, my gradient was considerably less steep at the origin , is that a problem?

As long as the gradient doesn't appear to be 0 (iirc people have lost marks for sketching inverse sine and stuff with a stationary point of inflection), and it resembles a tan graph, you should be ok. imo

[de]

It was certainly more than 0, but a bit less than one so I should be right. Thanks.

[zsteve]

For 7b I used more formal reasoning than 'drawing a graph' but I messed up as there were two cases.
I thus only got the first part, (0, pi/3). Would I get one mark?