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
Count change of signs to tell positive roots
then replace x with -x and evaluate, then count change in sign for negative roots
initially
+, -, -, +, +, -
3 changes
3 or 1 positive roots
replacing x with -x
-,-,+,+,-,-
2 changes
2 or 0 negative roots
B is answer
Answer: x=3
Step-by-step explanation: Step 1: Simplify both sides of the equation.
21x−5=7+17x
21x+−5=7+17x
21x−5=17x+7
Step 2: Subtract 17x from both sides.
21x−5−17x=17x+7−17x
4x−5=7
Step 3: Add 5 to both sides.
4x−5+5=7+5
4x=12
Step 4: Divide both sides by 4.
= 
So Final Answer: <u>x=3</u>
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To determine the slope, you can use the following formula:
(y2-y1)/(x2-x1)