Hi there!
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We are given:
cos(7x)cos(4x) = -1 - sin(7x)sin(4x)
Begin by moving all terms with variables to one side:
cos(7x)cos(4x) + sin(7x)sin(4x) = -1
The corresponding trig identity is cos(A - B). Thus:
cos(7x - 4x) = cos(7x)cos(4x) + sin(7x)sin(4x) = -1
cos(3x) = -1
cos = -1 at π, so:
3x = π
x = π/3
We can also find another solution. Let 3π = -1:
3x = 3π
x = π
Thus, solutions on [0, 2π) are π/3 and π.
12 x g + 1
Hope this help you
Answer:
Step-by-step explanation:
Think it’s - 1/3 not sure tho
5 and 6. square of 5 is 25 and square of 6 is 36. must be between 5 and 6
X=1.3
Hope this helps I not I’m truly sorry