Q. The product of two complex numbers z1 = 1 + i and z2 = 2 - i is?
-
A.
3 + i
-
B.
3 - i
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C.
2 + 3i
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D.
2 - 3i
Solution
z1 * z2 = (1 + i)(2 - i) = 2 - i + 2i - i^2 = 2 + 1 + i = 3 + i.
Correct Answer: A — 3 + i
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Q. The quadratic equation x^2 + 4x + 4 = 0 has:
-
A.
Two distinct real roots
-
B.
One real root
-
C.
No real roots
-
D.
Infinitely many roots
Solution
The discriminant is 0, indicating one real root (a repeated root).
Correct Answer: B — One real root
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Q. The quadratic equation x^2 + 6x + 9 = 0 has roots that are:
-
A.
Real and equal
-
B.
Real and distinct
-
C.
Complex
-
D.
None of these
Solution
The discriminant is 0, hence the roots are real and equal.
Correct Answer: A — Real and equal
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Q. The quadratic equation x^2 + kx + 16 = 0 has equal roots. What is the value of k?
Solution
For equal roots, the discriminant must be zero: k^2 - 4*1*16 = 0, solving gives k = -8.
Correct Answer: A — -8
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Q. The quadratic equation x^2 + px + q = 0 has roots 3 and -2. What is the value of p?
Solution
Using the sum of roots: p = -(3 + (-2)) = -1.
Correct Answer: B — 5
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Q. The quadratic equation x^2 - 3x + 2 = 0 can be factored as?
-
A.
(x-1)(x-2)
-
B.
(x-2)(x-1)
-
C.
(x+1)(x+2)
-
D.
(x-3)(x+2)
Solution
The equation factors to (x-1)(x-2) = 0.
Correct Answer: A — (x-1)(x-2)
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Q. The quadratic equation x^2 - 4x + 4 = 0 has how many distinct real roots?
Solution
The discriminant is 0, indicating one distinct real root.
Correct Answer: B — 1
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Q. The quadratic equation x^2 - 6x + 9 = 0 has how many distinct real roots?
-
A.
0
-
B.
1
-
C.
2
-
D.
Infinite
Solution
The discriminant is 0, indicating that there is exactly one distinct real root.
Correct Answer: B — 1
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Q. The quadratic equation x^2 - 6x + k = 0 has roots that differ by 2. What is the value of k?
Solution
Let the roots be r and r+2. Then, r + (r+2) = 6 and r(r+2) = k. Solving gives k = 10.
Correct Answer: B — 10
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Q. The real part of the complex number z = 4 - 3i is?
Solution
The real part of z = 4 - 3i is 4.
Correct Answer: A — 4
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Q. The roots of the equation 2x^2 - 4x + 1 = 0 are:
-
A.
1
-
B.
2
-
C.
1/2
-
D.
None of these
Solution
Using the quadratic formula, x = [4 ± √(16 - 8)] / 4 = [4 ± 2√2] / 4 = 1 ± √2/2. Hence, the roots are not simple fractions.
Correct Answer: C — 1/2
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Q. The roots of the equation 5x^2 - 20x + 15 = 0 are:
Solution
Using the quadratic formula, the roots are x = [20 ± √(400 - 300)] / 10 = [20 ± 10] / 10 = 3 and 1.
Correct Answer: B — 2
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Q. The roots of the equation x^2 + 2x + 1 = 0 are:
Solution
The equation can be factored as (x + 1)^2 = 0, giving a double root at x = -1.
Correct Answer: A — -1
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Q. The roots of the equation x^2 - 3x + 2 = 0 are:
-
A.
1 and 2
-
B.
2 and 3
-
C.
0 and 1
-
D.
None of these
Solution
Factoring gives (x-1)(x-2) = 0, so the roots are 1 and 2.
Correct Answer: A — 1 and 2
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Q. The sum of the roots of the equation 2x^2 - 3x + 1 = 0 is equal to what?
Solution
Using Vieta's formulas, the sum of the roots is -(-3)/2 = 3/2.
Correct Answer: B — 3/2
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Q. The sum of the roots of the equation 2x^2 - 4x + k = 0 is 3. What is the value of k?
Solution
The sum of the roots is given by -b/a = 4/2 = 2. Setting this equal to 3 gives k = 1.
Correct Answer: A — 1
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Q. The sum of the roots of the equation 3x^2 - 12x + 9 = 0 is:
Solution
The sum of the roots is given by -b/a = 12/3 = 4.
Correct Answer: C — 4
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Q. The sum of the roots of the equation x^2 - 7x + 10 = 0 is?
Solution
The sum of the roots is given by -b/a = 7/1 = 7.
Correct Answer: C — 7
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Q. The sum of the roots of the quadratic equation 2x^2 - 4x + k = 0 is 3. What is the value of k?
Solution
Using the sum of roots formula -b/a, we have 4/2 = 2, thus 2 + 1 = 3, so k = 1.
Correct Answer: B — 2
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Q. The sum of the roots of the quadratic equation 3x^2 - 12x + 9 = 0 is equal to what?
Solution
Using Vieta's formulas, the sum of the roots is -(-12)/3 = 4.
Correct Answer: B — 4
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Q. The sum of the roots of the quadratic equation 3x^2 - 12x + 9 = 0 is:
Solution
Using Vieta's formulas, the sum of the roots is -(-12)/3 = 4.
Correct Answer: B — 4
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Q. The sum of the roots of the quadratic equation 3x^2 - 12x + k = 0 is 4. What is the value of k?
Solution
Using Vieta's formulas, sum of roots = -b/a = 12/3 = 4, hence k = 8.
Correct Answer: C — 8
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Q. The sum of the roots of the quadratic equation x^2 - 7x + 10 = 0 is:
Solution
The sum of the roots is given by -b/a = 7/1 = 7.
Correct Answer: B — 7
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Q. The value of (1 + i)^2 is?
-
A.
2i
-
B.
2
-
C.
0
-
D.
1 + 2i
Solution
(1 + i)^2 = 1^2 + 2(1)(i) + i^2 = 1 + 2i - 1 = 2.
Correct Answer: B — 2
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Q. The value of sin^(-1)(-1) is:
Solution
sin^(-1)(-1) corresponds to the angle whose sine is -1, which is -π/2.
Correct Answer: A — -π/2
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Q. The value of sin^(-1)(√3/2) is:
-
A.
π/3
-
B.
π/6
-
C.
π/4
-
D.
π/2
Solution
sin^(-1)(√3/2) corresponds to the angle whose sine is √3/2, which is π/3.
Correct Answer: A — π/3
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Q. The value of tan^(-1)(√3) is:
-
A.
π/3
-
B.
π/4
-
C.
π/6
-
D.
π/2
Solution
tan^(-1)(√3) corresponds to the angle whose tangent is √3, which is π/3.
Correct Answer: A — π/3
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Q. What is the 7th term of the sequence defined by a_n = 2^n + 3^n?
-
A.
2187
-
B.
243
-
C.
256
-
D.
729
Solution
a_7 = 2^7 + 3^7 = 128 + 2187 = 2315.
Correct Answer: A — 2187
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Q. What is the argument of the complex number z = -1 + 0i?
Solution
The argument of z = -1 + 0i is arg(z) = π.
Correct Answer: A — π
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Q. What is the argument of the complex number z = -1 - i?
-
A.
-3π/4
-
B.
3π/4
-
C.
-π/4
-
D.
π/4
Solution
The argument of z = -1 - i is θ = tan^(-1)(-1/-1) = -3π/4.
Correct Answer: A — -3π/4
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