The formula for illuminance is given by
E = I / d^2
This formula only holds true for one-dimensional illuminance
The problem asks for the illuminance across the floor. We need to use two variables, x and y.
From Pythagorean Theorem
d^2 = x^2 + y^2
and from Trigonometry
x = d cos t
y = d sin t
The function for the illuminance can be represented by the composite function
E = I cos² t / x²
and
E = I sin² t / y²
The boundary of these functions is:
<span>0 < t < 8
So, the value of t must be in radians and not in degrees</span>
This does not look easy to factor, so I'd suggest using the quadratic formula:
-1 plus or minus sqrt( 1-4(3)(-5) )
x = -----------------------------------------------
2*3
-1 plus or minus sqrt(61)
= ------------------------------------
6
Thus, there are 2 real, unequal, irrational roots / solutions.
Correlation between x & y is 0.6125.
In probability theory and statistics, the cumulative distribution function of a real-valued random variable X, or simply the distribution function of X weighted by x, is the probability that X takes a value less than or equal to x.
The cumulative distribution function (CDF) of a random variable X is defined as FX(x)=P(X≤x) for all x∈R. Note that the subscript X indicates that this is the CDF of the random variable X. Also note that the CDF is defined for all x∈R. Let's look at an example.
Learn more about cumulative distribution here: brainly.com/question/24756209
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