Hello !
cos (a+b) = cos a cos b - sin a sin b
sin (a+b) = sin a cos b + sin b cos a
cos (a+b+c) = cos (a+(b+c))
cos (a+b+c) = cos a cos (b+c) - sin a sin (b+c)
cos (a+b+c) = cos a (cos b cos c - sin b sin c) - sin a (sin b cos c + sin c cos b)
cos (a+b+c)=cos a cos b cos c - cos a sin b sin c - sin a sin b cos c - sin a cos b sin c
Let Z be the reading on thermometer. Z follows Standard Normal distribution with mean μ =0 and standard deviation σ=1
The probability that randomly selected thermometer reads greater than 2.07 is
P(z > 2.07) = 1 -P(z < 2.07)
Using z score table to find probability below z=2.07
P(Z < 2.07) = 0.9808
P(z > 2.07) = 1- 0.9808
P(z > 2.07) = 0.0192
The probability that a randomly selected thermometer reads greater than 2.07 is 0.0192
Answer: D) 10
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Explanation:
I'm assuming points M and N are midpoints of segments FD and FE respectively. If that's the case, then segment DE is twice as long compared to segment MN. We consider MN to be a midsegment.
So,
DE = 2*(MN)
3x-2 = 2*(x+4)
3x-2 = 2x+8
3x-2x = 8+2
x = 10
