Answer:
c = 
Step-by-step explanation:
Given
R= 
Clear the radical by squaring both sides
R² = b² - 4ac ( subtract b² from both sides )
R² - b² = - 4ac ( multiply all terms by - 1 )
b² - R² = 4ac ( divide both sides by 4a )
= c
Answer:
He is incorrect in this statement because 38 and 40 both have factors, other than 1 x itself. Prime numbers are numbers the only have 1 factor pair, and that is 1 x itself. Factors are the numbers you multiply to get the end result, and an example is 10x4=40. The factors of 40 are 8x5, 4x10, 2x20, and of course, 1x40. The factors of 38 are 2x19, and 1x38.
For a function to have a derivative in a point has to be continuous at the point, that is, it has to be defined at that point, other wise the derivative would be meaningless.
<em>z</em> = 3<em>i</em> / (-1 - <em>i</em> )
<em>z</em> = 3<em>i</em> / (-1 - <em>i</em> ) × (-1 + <em>i</em> ) / (-1 + <em>i</em> )
<em>z</em> = (3<em>i</em> × (-1 + <em>i</em> )) / ((-1)² - <em>i</em> ²)
<em>z</em> = (-3<em>i</em> + 3<em>i</em> ²) / ((-1)² - <em>i</em> ²)
<em>z</em> = (-3 - 3<em>i </em>) / (1 - (-1))
<em>z</em> = (-3 - 3<em>i </em>) / 2
Note that this number lies in the third quadrant of the complex plane, where both Re(<em>z</em>) and Im(<em>z</em>) are negative. But arctan only returns angles between -<em>π</em>/2 and <em>π</em>/2. So we have
arg(<em>z</em>) = arctan((-3/2)/(-3/2)) - <em>π</em>
arg(<em>z</em>) = arctan(1) - <em>π</em>
arg(<em>z</em>) = <em>π</em>/4 - <em>π</em>
arg(<em>z</em>) = -3<em>π</em>/4
where I'm taking arg(<em>z</em>) to have a range of -<em>π</em> < arg(<em>z</em>) ≤ <em>π</em>.
