Answer:
θ = 2 π n_1 + π/2 for n_1 element Z or θ = 2 π n_2 for n_2 element Z
Step-by-step explanation:
Solve for θ:
cos(θ) + sin(θ) = 1
cos(θ) + sin(θ) = sqrt(2) (cos(θ)/sqrt(2) + sin(θ)/sqrt(2)) = sqrt(2) (sin(π/4) cos(θ) + cos(π/4) sin(θ)) = sqrt(2) sin(θ + π/4):
sqrt(2) sin(θ + π/4) = 1
Divide both sides by sqrt(2):
sin(θ + π/4) = 1/sqrt(2)
Take the inverse sine of both sides:
θ + π/4 = 2 π n_1 + (3 π)/4 for n_1 element Z
or θ + π/4 = 2 π n_2 + π/4 for n_2 element Z
Subtract π/4 from both sides:
θ = 2 π n_1 + π/2 for n_1 element Z
or θ + π/4 = 2 π n_2 + π/4 for n_2 element Z
Subtract π/4 from both sides:
Answer: θ = 2 π n_1 + π/2 for n_1 element Z
or θ = 2 π n_2 for n_2 element Z
<span> joint variation
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</span>
Answer:
The value of ROE that will be exceeded by 78% of the firms is -1.77%.
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean
and standard deviation
the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
The mean ROE for the firms studied was 14.93% and the standard deviation was 21.74%. This means that 
What value of ROE will be exceeded by 78% of the firms?
This is the value of X when Z has a pvalue of 1-0.78 = 0.22.
This is 
So:




The value of ROE that will be exceeded by 78% of the firms is -1.77%.
<span>here we can use Pythogoras' theorem.
in right angled triangles the square of the hypotenuse is equal to the sum of the squares of the other 2 sides.
hypotenuse is 19 cm. One side is 13 cm and we need to find the length of the third side.
19</span>²<span> = 13</span>²<span> + X</span>²<span>
X - length of the third side
361 = 169 + X</span>²<span>
X</span>²<span> = 361 - 169
X</span>²<span> = 192
X = 13.85 the length of third side rounded off to the nearest tenth is 13.9 cm</span>
Answer:
81
Step-by-step explanation:
the formula for an arithmetic sequence:
aₙ = a₁ + (n-1)d
where aₙ = the nth term
a₁ = the 1st term = -3
n = the term number = 13
d = the common difference = 7
Plugging in those values into the formula to find a₁₃:
a₁₃ = -3 + (13-1)7
= -3 + (12)7
= -3 + 84
= 81