Answer:
i
Step-by-step explanation:
i = 
i^2 = -1
i^3 = -i
i^4 = 1
(Make sure you know your exponent rules)

<u><em>Answer:</em></u>
The bird is approximately 9 ft high up in the tree
<u><em>Explanation:</em></u>
The required diagram is shown in the attached image
Note that the tree, the cat and the ground form a right-angled triangle
<u>Therefore, we can apply special trigonometric functions</u>
<u>These functions are as follows:</u>

<u>Now, taking a look at our diagram, we can note the following:</u>
α = 25°
The opposite side is the required height (x)
The adjacent side is the distance between the cat and the tree = 20 ft
Therefore, we can use the <u>tan function</u>
<u>This is done as follows:</u>
which is 9 ft approximated to the nearest ft
Hope this helps :)
Step-by-step explanation:
1. a² - ( b ² - 2bc + c² ) = a ² - b ² + 2bc - c²
2. 8p² - 18 q²
3. 3ab² - c²d + 3ab - b²c²
4. x² - 2x + 1
All real numbers greater than or equal to -8. You can see 3 is a minimum point because at 3 the numbers start to increase again. -8 is the lowest number and the function is increasing as x approaches infinity starting at 3.