Answer:
n = π/6, π/4, 3π/4, 5π/6
Step-by-step explanation:
sin(3n) − sin n = cos(2n)
Use double and triple angle formulas:
(3 sin n − 4 sin³ n) − sin n = 1 − 2 sin² n
2 sin n − 4 sin³ n = 1 − 2 sin² n
4 sin³ n − 2 sin² n − 2 sin n + 1 = 0
Factor by grouping:
2 sin² n (2 sin n − 1) − (2 sin n − 1) = 0
(2 sin² n − 1) (2 sin n − 1) = 0
Solve:
2 sin² n − 1 = 0
2 sin² n = 1
sin² n = 1/2
sin n = √2/2
n = π/4, 3π/4
2 sin n − 1 = 0
2 sin n = 1
sin n = 1/2
n = π/6, 5π/6
Answer:
B.
Step-by-step explanation:
C= 20 degrees Celsius
20 x 9/5 = 180/5
180 divided by 5 = 36 degrees celsius
Then you do 36 degrees celsius + 32 and you get 68.
So therefore 20 degrees celsius is eqivalent to 68 degrees Fahrenheit.
Answer:
The number is 492,875.
Step-by-step explanation:
Given:
A number that is = 
Place value of 4 = 
Place value is ten thousands.
We have to identify the number where the place value of 4 is 10 times of the given number.
Numbers given:
284,796 or 327,498 or 492,875 and 742,186.
Lets see the place value of 4 in each of the number.
⇒
-
place value of
is
. - Place value of 4 is thousands.
⇒
place value of
is
.- Place value of 4 is hundreds.
⇒
place value of
is
.- Place value of 4 is hundred thousands.
⇒
place value of
is
.- Place value of 4 is ten thousands.
Notes:
Ten thousands multiplied with ten is hundreds thousand.
⇒ 
So,
The number which has digit 4 as hundred thousands place values is 492,875.