We can use tan(x) = sin(x)/cos(x). Plug in numbers to get:
tan(x+pi/2) = sin(x+pi/2)/cos(x+pi/2)
Here, you can use the sin and cos addition identity:
tan(x+pi/2) = (sin(x)cos(pi/2)+cos(x)sin(pi/2))/(cos(x)cos(pi/2)+sin(x)sin(pi/2))
If you simplify this, you get:
0+cos(x)/0-sin(x)
Which is the definition of cot(x). But, we can't forget about the '-' sign, so, the answer is -cot(x)
Answer:


Step-by-step explanation:
Given

Solving (a): The cost function:
From the given parameter, it shows that the number of floor has no effect on the floors.
So, represent the floors with x.
The cost function is:

Solving (b): The slope and its interpretation
A function is represented as:

Where:

By comparing:
to 

So:

<em>What it means is that, no matter the number of floors, the cost remains unchanged.</em>
This is an isosceles triangle, so both legs are of length 5√2.
Use the Pyth. Thm. to find the length of the hypotenuse. Square 5√2 and double the result: 25(2) = 50; twice 50 is 100. The square of the length of the hyp. is 100, and so the length of the hyp is sqrt(100), or 10 (answer).
Answer: a) x < 3
b) 3, 4, 5, 6
c) x > 6
<u>Step-by-step explanation:</u>
First you need to understand the symbols:
< means less than (represented by an open dot, left arrow)
≤ means less than or equal to (represented by a closed dot, left arrow)
> means greater than (represented by an open dot, right arrow)
≥ means greater than or equal to (represented by a closed dot, right arrow)
a) We have a closed dot and a left arrow so we need to use <
We write this inequality as: x < 3
b) y is BETWEEN 2 and 6 (not including 2 but including 6)
2 <u> </u><u>3 </u> <u> 4 </u> <u> 5 </u> 6
c) 3x + 7 > x + 19
2x + 7 > 19 subtracted x from both sides
2x > 12 subtracted 7 from both sides
x > 6 divided both sides by 2