<span>2x^2 - 2x - 1 = 0 a = 2, b = -2, c = -1 b^2 - 4ac = (-2)^2 - 4(2)(-1) = 4 + 8 = 12
so the answer is 12
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Answer:
96 ways
Step-by-step explanation:
Given

Required
Ways to divide it into period of seconds
What this question implies is to determine the total number of factors of 86400
To start with, we determine the prime factorization of 86400
To do this, we continually divide 86400 by 2; when it can not be further divided, we divide by 3, then 7, then 11...












This implies that:

The number of factors d is the solved by:

Where

By comparison:



So:



<em>Hence, there are 96 total ways</em>
Answer:
119.05°
Step-by-step explanation:
In general, the angle is given by ...
θ = arctan(y/x)
Here, that becomes ...
θ = arctan(9/-5) ≈ 119.05°
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<em>Comment on using a calculator</em>
If you use the ATAN2( ) function of a graphing calculator or spreadsheet, it will give you the angle in the proper quadrant. If you use the arctangent function (tan⁻¹) of a typical scientific calculator, it will give you a 4th-quadrant angle when the ratio is negative. You must recognize that the desired 2nd-quadrant angle is 180° more than that.
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It may help you to consider looking at the "reference angle." In this geometry, it is the angle between the vector v and the -x axis. The coordinates tell you the lengths of the sides of the triangle vector v forms with the -x axis and a vertical line from that axis to the tip of the vector. Then the trig ratio you're interested in is ...
Tan = Opposite/Adjacent = |y|/|x|
This is the tangent of the reference angle, which will be ...
θ = arctan(|y| / |x|) = arctan(9/5) ≈ 60.95°
You can see from your diagram that the angle CCW from the +x axis will be the supplement of this value, 180° -60.95° = 119.05°.
Answer:
116 cm²
Step-by-step explanation:
The area of a circle = πr² ← r is the radius
shaded area = external area - internal area
= π × 6.5² - π × 2.3²
= π( 42.25 - 5.29)
= π × 36.96 ≈ 116 cm²
Answer:
1) x= 3i, x= - 3i
2) x= +i
, x = - i
Step-by-step explanation:
1) x^2+9=0
(x+3i)(x-3i)=0
x= 3i, x=-3i
2) x^2-4=-11
x^2=-7
x= ±i
x= +i
, x = - i
hope this helps!! :))