When roots of polynomials occur in radical form, they occur as two conjugates.
That is,
The conjugate of (a + √b) is (a - √b) and vice versa.
To show that the given conjugates come from a polynomial, we should create the polynomial from the given factors.
The first factor is x - (a + √b).
The second factor is x - (a - √b).
The polynomial is
f(x) = [x - (a + √b)]*[x - (a - √b)]
= x² - x(a - √b) - x(a + √b) + (a + √b)(a - √b)
= x² - 2ax + x√b - x√b + a² - b
= x² - 2ax + a² - b
This is a quadratic polynomial, as expected.
If you solve the quadratic equation x² - 2ax + a² - b = 0 with the quadratic formula, it should yield the pair of conjugate radical roots.
x = (1/2) [ 2a +/- √(4a² - 4(a² - b)]
= a +/- (1/2)*√(4b)
= a +/- √b
x = a + √b, or x = a - √b, as expected.
Answer: C
Step-by-step explanation: For a function, each x-coordinate corresponds to exactly one y-coordinate.
To determine whether the graph shown here
is a function, we can use the vertical line test.
The vertical line test tells us that if each x-coordinate on the graph corresponds to exactly one y-coordinate, then any vertical line that we draw on the graph should hit the graph at only one point.
For the graph show here, any vertical line that you draw with hit the graph at only one point which means it does pass the vertical line test.
So this graph is a <em>function</em>.
Answer:
15x +10y
Step-by-step explanation:
Just multiply 5x and 2y times 5 and don't combine them since they are different terms.
60/2 equals 30 then 30x4 is 120. Is parents give him a 120$
Step-by-step explanation:
Let's rewrite the given equation such that only y is on the left side and everything else on the right side:
Simplifying this by dividing by 6, we get
This line has a slope of -1/2, which means that a line perpendicular to this has a slope of 2 (i.e., negative reciprocal). So we can write its equation as
This is the slope-intercept form of the equation of the line perpendicular to our given line. To complete this form, we need to find the value of b. Since this line passes through (1, -7), put these numbers into our equation to get
Therefore, the slope-intercept form of the equation can be written as
