There's a site called m.a.t.h.w.a.y, and you can type in those functions in order to get the graph ;)
The confidence interval would be (10.44, 12.16). This means that if we take repeated samples, the true mean lies in 90% of these intervals.
To find the confidence interval, we use:

We first find the z-value associated with this. To do this:
Convert 90% to a decimal: 90% = 90/100 = 0.9
Subtract from 1: 1-0.9 = 0.1
Divide by 2: 0.1/2 = 0.05
Subtract from 1: 1-0.05 = 0.95
Using a z-table (http://www.z-table.com) we see that this is directly between two z-scores, 1.64 and 1.65; we will use 1.645:
We are given with the expression <span>tan2x / x</span> and asked to evaluate the expression to limit as theta approaches zero. In this case, we substitute first zero. The answer is zero over zero. This is indeterminate so we derive the terms accdg to L'hopital's rule. The derivative is 2 sec^2 2x/1. cos 2x is 1 so is sec^2 2x. Hence the answer is 2.
Answer:
c and b
Step-by-step explanation: