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:
a 72
Step-by-step explanation:
9x10=90, so in total he has 90 pencils. if he loses 18 of them that's 90-18 which is 72.
Answer:
5z^2-7z^4
Step-by-step explanation:
Umm I didn't get a domain.... No solutions were found...
Answer:2c^2+5c+4
Step-by-step explanation:
About 92% sure this is the correct answer hun! Good luck!!
