Answer:
-60/7 or -8 4/7 would be the answer
Step-by-step explanation:
sin(2x) = 2sin(x)cos(x)
2sin(x)cos(x) - cos(x) = 0
so one solution is cos(x) = 0.
=> x = pi/2 and 3pi/2 (90° and 270°)
for cos(x) <> 0 we have then
2sin(x) - 1 = 0
2sin(x) = 1
sin(x) = 1/2
=> x = pi/6 and 5pi/6 (30° and 150°)
SOLUTION:
Case: Percentages
Method:
The sale price after 30% off is $6800
Let the original price be 'x'
30% off means 70% of the original price

Final answer: (Nearest cents)
The original price was $9714.29
There are 12 ways he can pay this amount using the notes he has the answer is 12.
<h3>What are permutation and combination?</h3>
A permutation is the number of different ways a set can be organized; order matters in permutations, but not in combinations.
Let x be the number of Rs10 notes and y be the Rs20 note
10x + 20y = 220
The whole number of x and y which satisfy the above equation:
x = 0, y =11
x = 2, y =10
x = 4, y =9
x = 6, y =8
x = 8, y =7
x = 10, y =6
x = 12, y =5
x = 14, y =4
x = 16, y =3
x = 18, y =2
x = 20, y =1
x = 22, y =0
Total number of ways = 12
Thus, there are 12 ways he can pay this amount using the notes he has the answer is 12.
Learn more about permutation and combination here:
brainly.com/question/2295036
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