REVIEW OF CHAPTER: THEORY OF EQUATIONS
P(x) =
long division synthetic division x-r |
example 1 x + 3 x-(-3) r = -3 |
example 2 x-3 r=3 |
1) P(x) = ax + b r = 0 1 answer & 1 factor
P(x) = a(x-r)
P(x) = 3x - 4 P(x) = 3(x-)
3x - 4 = 0
3x = 4
x =
2) P(x) = ax2 + bx + c
solving equations roots
(ans)
and finding zeros of
P(x) zeros (ans)
a. 3 methods
1. completing the square
2. factoring
3. quad formb. sum of 2 zeros r1 + r2 =
product of 2 zeros r1 r2 =c. discriminant
b2 - 4ac > 0 real and unequal
b2 - 4ac= 0 real and equal
b2 - 4ac< 0 complex conj.d. expressions quadratic in form
x4 + 5x2 + 6 = 0 4th deg = 4 ans.
let x2 = me. radical equations and also equations to fractional powers
= x-2 x2/3 + 3x1/3 + 4 = 0
let m = x 1/3
MUST CHECK ALL ANSWERSf. P(x) = ax2 + bx + c
P(x) = a(x - r1)(x - r2) 2 factors
3) General P(x) = a(x - r1)(x - r2)(x - r3)(x - rn)
nth degree - "n" zeros = "n" linear factors
a. Remainder Theorem - If P(x) is divided by x - r and R is the remainder then P(r ) = R
b. Factor Theorem - If x - r is a factor of P(x), then R = 0 (So P® = 0 if x - r is a factor)
c. P(x) with real coefficients (no i's) If r is a zero, so is r (really, only pertains to complex #'s)
d. P(x) with integral coefficients (whole #'s) If rational zeros exist, they are in the form of p/q, where p is a factor of a0(constant) and q is a factor of an(leading coefficient)