Answer:
x = π/4 and 5π/4
Step-by-step explanation:
Given the expression;
2cos²x - 1 = 0
2cos²x = 0+1
2cos²x = 1
cos²x = 1/2
cos x = ±√1/2
cos x = ±0.7071
x = arccos(±0.7071)
x = ±45 degrees
Convert to radians
Sence 180° = π rad
45° = x
x = 45π/180
x = π/4
If x = -45°
Since cos is negative in the 3rd quadrant
x = 180 + 45
x = 225°
x = 225π/180
x = 45π/36
x = 5π/4
Answer:
1332 i think is how it will be writen
Step-by-step explanation:
Answer:
i think it's circumference
Step-by-step explanation:
<h3>
Answer: Third choice. 
</h3>
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Explanation:
SAS stands for Side Angle Side. Note how the angle is between the two sides. To prove the triangles congruent with SAS, we need to know two sides and an angle between them.
We already see that BC = CD as shown by the tickmarks. Another pair of sides is AC = AC through the reflexive theorem.
The missing info is the angle measures of ACB and ACD. If we knew those angles were the same, then we could use SAS to prove triangle ACB is congruent to triangle ACD.
It turns out that the angles are congruent only when they are 90 degrees each, leading to AC being perpendicular to BD. We write this as
. The upside down T symbol meaning "perpendicular" or "the two segments form a right angle".
Well there really wouldn't be a combo since everything is different so I'm saying nun? that's what I'm going with. ( If this is wrong correct me )