There are two sides in a coin so the chance of getting tails is 1/2, which would be 0.5.
I'm not sure tho.
tan2x*cotx - 3 = 0
We know that: tan2x = sin2x/cos2x and cotx = cosx/sinx
==> sin2x/cos2x *cosx/sinx = 3
Now we know that sin2x = 2sinx*cosx
==> 2sinxcosx/cos2x * cosx/sinx = 3
Reduce sinx:
==> 2cos^2 x/ cos2x = 3
Now we know that cos2x = 2cos^2 x-1
==> 2cos^2 x/(2cos^2 x -1) = 3
==> 2cos^2 x = 3(2cos^2 x -1)
==> 2cos^2 x = 6cos^2 x - 3
==> -4cos^2 x= -3
==> 4cos^2 x = 3
==> cos^2 x = 3/4
==> cosx = +-sqrt3/ 2
<span>==> x = pi/6, 5pi/6, 7pi/6, and 11pi/6</span>
There are 3,300 different ways to select the committee.
First, we need to determine the total number of ways the 6 members can be selected.
For the chair and vice chair, it would be 5 x 4 = 20, but then that has to be divided by 2. (Because the order doesn't matter)
20 / 2 = 10
For the rest, it would be 11 x 10 x 9 x 8 = 7920, but again divide it by 4! because the order doesn't matter.
7920 / 24 = 330
To find the total ways for both, multiply 10 by 330 to get 3300.
<h2>-3n where n can be (-∞ to +∞)</h2><h2>hope it helped :-)</h2>
Answer:
18
Step-by-step explanation:
Since this is a multiple choice question, I will employ the guess and check method - meaning I will check each answer one by one.
Variable x = dimes = $0.10
Variable y = quarters = $0.25
Set up a system of equations:
x + y = 38
x(0.10) + y(0.25) = 6.80
Plug in each choice into the second equation. You can find the number of quarters that correspond to each number of dimes by using the first equation.
20 dimes:
20 + y = 38
y = 18
20(0.10) + 18(0.25) = 6.80
2 + 4.5 = 6.80
6.5 does not equal 6.80
Because dimes (x) are worth less than quarters (y), this result tells us the answer will be less than 20 dimes as with 20 or more we have less than $6.80. Another example just to show this is true:
38 dimes:
38 + y = 38
y = 0
38(0.10) + 0(0.25) = 6.80
3.8 + 0 = 6.80
3.8 does not equal 6.80.
Since x is worth less than y, we need more of y rather than x. Adding more x will only mean we will get a lower price. Adding more y will mean we get a higher price which is what we need. So only solve for x that is less than 20.
6
6 + y = 38
y = 22
6(0.10) + 32(0.25) = 6.80
0.60 + 8 = 8.60
8.60 does not equal 6.80.
This result is higher than what we wanted (6.80) which means we need more x. Now we only have to solve for x numbers that are greater than 6 and less than 20.
18
18 + y = 38
y = 20
18(0.10) + 20(0.25) = 6.80
1.8 + 5 = 6.8
6.8 does equal 6.8.
Correct!
