Sagot :
=> x - π/9 = π/4 + 2kπ, where k is an integer or x - π/9 = 3π/4 + 2kπ, where k is an integer => x = 13π/36 + 2kπ, where k is an integer or x = 31π/36 + 2kπ, where k is an integer;
Answer:
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Step-by-step explanation:
Note that 1/√(2) is equal to √(2)/2:
1/√(2) = √(2)/2
So we're given that sin(x-20) = √(2)/2
The only place on the unit circle where sin() is equal to √(2)/2 is at π/4 and 3π/4.
That means the value inside the sine must be equal to π/4 and 3π/4:
since sin(π/4) = √(2)/2 and sin(π/4) = √(2)/2
then,
sin(π/4) = sin(x-20) and sin(π/4) = sin(x-20)
You set the inside of the parentheses equal to each other and solve for x.
You can also add a +2πk at the end since all sinusoidal graph repeats every 2π.