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Free_Kalibri [48]
3 years ago
13

Solve the equation 2 cos ( x ) + 1 = 0 2 cos x + 1 = 0 , 0 ≤ x ≤ 2 π 0 ≤ x ≤ 2 π . Show all of your work

Mathematics
1 answer:
TiliK225 [7]3 years ago
8 0

Answer:

2π/3, 4π/3

Step-by-step explanation:

I interpret your question as asking us to solve the equation

2cos(x) + 1 = 0

2cos(x) = -1

cos(x) = -½x  

x = arccos(-½), 0 ≤ x ≤2π

Since the cosine is negative, x must be in the second or third quadrant.

Referring to the unit circle, we find that

x = 2π/3 (120°) or x = 4π/3 (240°)

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Read 2 more answers
The height of a triangle is 7 cm longer than its base.
katrin [286]
A) Height -7 = base
B) .5 * height * base = 60
Substituting A into B
B) .5 * height * (height -7) = 60
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**************************************************************
Double-Check
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6 0
3 years ago
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Sholpan [36]

Answer:

x = 2

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Step-by-step explanation:

2x + 2y = -2, then 2y = -2 - 2x

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so:

-2 - 2x = 3x - 12

add 2x and 12 to each side of the equation:

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8 0
2 years ago
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Answer:

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Step-by-step explanation:

by simple substitution

7 0
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