Since the polynomial has three zeroes it has a degree of 3. So we have:
(x - -5)[x - (2 + i)][x - (2 - i)]
= (x + 5)[(x - 2) - i][(x - 2) + i]
= (x + 5)[(x - 2)2 - i2]
= (x + 5)[x2 - 2(x)(2) + 22 - (-1)]
= (x + 5)(x2 - 4x + 4 + 1)
= (x + 5)(x2 - 4x + 5)
= x(x2 - 4x + 5) + 5(x2 - 4x + 5)
= x3 - 4x2 + 5x + 5x2 - 20x + 25
= x3 + x2 - 15x + 25
Thus,
P(x) = x3 + x2 - 15x + 25
1.75 + 1.75i7i/2 + 2i = 3.5i + 2i = 5.5i
The four roots are:1 + 2i, 1 - 2i, 3i and -3i.
-5-7=-126i-8i=-2i-12-2i is your final answer
8.2462 (rounded)
To solve this type of problem, multiply both the numerator and denominator by the conjugate of the denominator. (2 - 4i) / (4 + 2i) = (2 - 4i)(4 - 2i) / (4 + 2i)(4 - 2i) then expand all the terms, and simplify. = (8 - 20i + 8i2) / (16 - 4i2) = (8 - 20i - 8) / (16 + 4) = -20i / 20 = -i Which in the required answer format becomes, 0 + i.
(x - u)*(x - u)*(x + 2i)*(x - 2i) = (x2 - 2xu + u2)*(x2 + 4) = x4 - 2x3u + x2(u2 + 4) - 8xu + 4u2
Not necessarily, take for example the equation x^2=5-12i. Then, 3-2i satisfies the equation. However, 3+2i does not because (3+2i)^2 = 5+12i.
f(x)=x3-3x2-5x+39=(x+3)(x2-6x+13) It has three roots. One of which is x=-3. Using the quadratic equation: x = (6 +/- √(-16))/2 x = (6 +/- 4i)/2 = (3 +/- 2i) so, x=-3, x=3+2i, or x=3-2i
10 + 6i and 7 + 2i = 10 + 6i + 7 + 2i = 17 + 8i
1.75 + 1.75i7i/2 + 2i = 3.5i + 2i = 5.5i
Sort of... but not entirely. Assuming the polynomial's coefficients are real, the polynomial either has as many real roots as its degree, or an even number less. Thus, a polynomial of degree 4 can have 4, 2, or 0 real roots; while a polynomial of degree 5 has either 5, 3, or 1 real roots. So, polynomial of odd degree (with real coefficients) will always have at least one real root. For a polynomial of even degree, this is not guaranteed. (In case you are interested about the reason for the rule stated above: this is related to the fact that any complex roots in such a polynomial occur in conjugate pairs; for example: if 5 + 2i is a root, then 5 - 2i is also a root.)
It is 3 minus 2i
The question has a simple answer only if the polynomial has rational coefficients. However, the question does not state that it has rational coefficients so it is not valid to assume that is the case. So, suppose the third root is p. Then the polynomial is (x + 3)*(x - 3 + 2i)*(x - p) = (x2 + 2xi - 9 + 6i)*(x - p) = x3 + (2i - p)x2 - (2pi - 6i + 9)x + (9p + 6pi)
The four roots are:1 + 2i, 1 - 2i, 3i and -3i.
(-2 + 3i) + (-1 - 2i) = -2 + 3i - 1 - 2i = -2 - 1 + 3i - 2i = -3 + i
-5-7=-126i-8i=-2i-12-2i is your final answer
The complete ionic equation for this reaction is: 2H⁺(aq) + SO₄²⁻(aq) + Ca²⁺(aq) + 2I⁻(aq) → CaSO₄(s) + 2H⁺(aq) + 2I⁻(aq)