Answer:
0.4546
Step-by-step explanation:
nCr = n!/(n-r)!r!
Number of ways of selecting the four defective voltage regulators from 12 = 12C4 = 12!/(12-4)!4! = 12!/8!4! = (12 *11*10*9)/(4*3*2*1)
12C4 = 495 ways
Number of ways of selecting 2 defectives from line 1 = 6C2 * 6C2
6C2 = 6!/(6-2)!2! = 6!/4!2! = (6*5)/(2*1) = 15
6C2 * 6C2 = 15*15 = 225 ways
Probability = Number of possible outcomes/ Number of total outcomes
Probability that exactly 2 of the defective regulators came from line 1 = 225/40.95 = 0.4546
![\bf f(x)=(x-6)e^{-3x}\\\\ -----------------------------\\\\ \cfrac{dy}{dx}=1\cdot e^{-3x}+(x-6)-3e^{-3x}\implies \cfrac{dy}{dx}=e^{-3x}[1-3(x-6)] \\\\\\ \cfrac{dy}{dx}=e^{-3x}(19-3x)\implies \cfrac{dy}{dx}=\cfrac{19-3x}{e^{3x}}](https://tex.z-dn.net/?f=%5Cbf%20f%28x%29%3D%28x-6%29e%5E%7B-3x%7D%5C%5C%5C%5C%0A-----------------------------%5C%5C%5C%5C%0A%5Ccfrac%7Bdy%7D%7Bdx%7D%3D1%5Ccdot%20e%5E%7B-3x%7D%2B%28x-6%29-3e%5E%7B-3x%7D%5Cimplies%20%5Ccfrac%7Bdy%7D%7Bdx%7D%3De%5E%7B-3x%7D%5B1-3%28x-6%29%5D%0A%5C%5C%5C%5C%5C%5C%0A%5Ccfrac%7Bdy%7D%7Bdx%7D%3De%5E%7B-3x%7D%2819-3x%29%5Cimplies%20%5Ccfrac%7Bdy%7D%7Bdx%7D%3D%5Ccfrac%7B19-3x%7D%7Be%5E%7B3x%7D%7D)
set the derivative to 0, solve for "x" to get any critical points
keep in mind, setting the denominator to 0, also gives us critical points, however, in this case, the denominator will never be 0, so... no critical points from there
there's only 1 critical point anyway, and do a first-derivative test on it, check a number before it and after it, to see what sign the derivative has, and thus, whether the graph is going up or down, to check for any extrema
Answer:
is that even possible.
Step-by-step explanation:
Answer:
one point
Step-by-step explanation:
A system of two linear equations will have one point in the solution set if the slopes of the lines are different.
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When the equations are written in the same form, the ratio of x-coefficient to y-coefficient is related to the slope. It will be different if there is one solution.
- ratio for first equation: 1/1 = 1
- ratio for second equation: 1/-1 = -1
These lines have <em>different slopes</em>, so there is one solution to the system of equations.
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<em>Additional comment</em>
When the equations are in slope-intercept form with the y-coefficient equal to 1, the x-coefficient is the slope.
y = mx +b . . . . . slope = m
When the equations are in standard form (as in this problem), the ratio of x- to y-coefficient is the opposite of the slope.
ax +by = c . . . . . slope = -a/b
As long as the equations are in the same form, the slopes can be compared by comparing the ratios of coefficients.
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If the slopes are the same, the lines may be either parallel (empty solution set) or coincident (infinite solution set). When the equations are in the same form with reduced coefficients, the lines will be coincident if they are the same equation.