Answer:
Step-by-step explanation:
By using the cos square identity in trigonometry i.e., cos2ϴ = 1 – sin2 ϴ, we can evaluate the exact value of cos(33 ). For calculating the exact value of cos(∏/6), we have to substitute the value of sin(30°) in the same formula.
cos(30°) = √1 – sin230°
The value of sin30° is 1/2 (Trigonometric Ratios)
cos(30°) = √1 – (1/2)2
cos(30°) = √1 – (1/4)
cos(30°) = √(1 * 4 – 1)/4
cos(30°) = √(4 – 1)/4
cos(30°) = √3/4
Therefore, cos(30°) = √3/2
Answer:
29037.036 miles
Step-by-step explanation
There are two possible ways to solve this problem.
The first option starts with the $2800 dollars for the years. You first want to divide this by $2.70, because it will give you the amount of gallons of gas you can buy with that money.
2800/2.70 = 1037.037
This means you can buy 1037.037 gallons of gas in the year. Now you need to convert this to miles by multiplying by the amount of miles per gallon.
1037.037 x 28 = 29037.036 gallons
The second way to look at this is dimensional analysis. If you have learned this, then continue on reading this, but if you haven't I might only confuse you. I only suggest this because it can make it a little easier.
For the dimensional analysis, you need to start with what you are given and move to what you need to know, so you will start with the $2800 dollars and move to gallons. $2.70 per gallon and 28 miles per gallon are your conversion factors.
Set it up like this:
This allows the equation to be more organized, and you can check your work by canceling the units.
Hope this helps.
Answer:
256
Step-by-step explanation:
A calculator works well for this.
_____
None of the minus signs are subject to the exponents (because they are not in parentheses, as (-1)^5, for example. Since there are an even number of them in the product, their product is +1 and they can be ignored.
1 to any power is still 1, so the factors (1^n) can be ignored.
After you ignore all of the things that can be ignored, your problem simplifies to ...
(2^2)(2^-3)^-2
The rules of exponents applicable to this are ...
(a^b)^c = a^(b·c)
(a^b)(a^c) = a^(b+c)
Then your product simplifies to ...
(2^2)(2^((-3)(-2)) = (2^2)(2^6)
= 2^(2+6)
= 2^8 = 256
