Mathematics · Reasoning
Algebraic Expressions
183 Questions
Algebraic expressions form the foundation of mathematics, involving variables, constants, and arithmetic operations. This topic includes evaluating coefficients, solving proportional relationships, and understanding boolean logic. It is widely tested across various competitive exams to assess analytical skills.
Variable evaluationExpression coefficientsBoolean logic variablesDirect proportionalityProgramming expressions
Algebraic Expressions Questions
A
Correct answer
Explanation
1*x^2 + 2*x + 6 = 5*y + 6. If x=8, 64+16+6 = 86. If y=16, 5*16+6 = 86. The equation holds for x=8 and y=16.
B
Correct answer
Explanation
The condition f(x, y, z) = f(x', y', z') means the function is invariant under complementation of all inputs. There are 2^3 = 8 possible input combinations, which can be grouped into 4 pairs of (x, y, z) and (x', y', z'). For each pair, the function can take 2 values (0 or 1), leading to 2^4 = 16 possible functions.
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x.x = 1
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x (y + z) = (x + y) (x + z)
-
x + xz = x
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x + y = y + x
D
Correct answer
Explanation
Option D represents the Commutative Law of Boolean algebra, which states that x + y = y + x. Option A is incorrect (x.x = x), Option B is incorrect (distributive law is x + yz = (x + y)(x + z)), and Option C is incorrect (x + xz = x is actually the Absorption Law, but the question asks for a general identity).
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may or may not yield the same value
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must yield the same value
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must yield different values
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Cannot be said
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None of these
A
Correct answer
Explanation
Since / and * operators have the same hierarchy and one can do / and * operations alternately, it may or may not yield the same value.
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-12x2y3
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12x2y3
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-12x2
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12y3
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None of these
A
Correct answer
Explanation
Coefficient of z in -12 x2y3z is -12x2y3.
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3y + x
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3x + y
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x + y
-
None of these
A
Correct answer
Explanation
The addition of 3 times y and x gives 3y + x.
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x = 2, y = 3
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x = 4, y = 3
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x = 4, y = 9
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x = 2, y = 9
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None of these
C
Correct answer
Explanation
Take = a, = b.
Then, the equations will become 4a – 3b = 1 ……..(1)
And a + ab = 3.5 ………(2)
(1) × 3 + (2)⇒ a = and by substituting a in either (1) and (2), we can get b = .
a = = ⇒ x = 4 and b = = ⇒ y = 9
Option 3 is correct.
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x = 3, y = 2
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x = 2, y = 3
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x = 4, y = 5
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x = 5, y = 4
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x = 1, y = 4
A
Correct answer
Explanation
Take 1/x - y = a and 1/3x - 2y = b
a + 5b = 2 ……(1)
15b – 2a = 1 ……(2)
(1) × 2 + (2) ⇒ b = So, a = 1.
x – y = = 1 ……..(3)
and 3x – 2y = = 5 ……(4)
So, x = 3; y = 2
Option 1 is correct.
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2 and 3
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1 and 2
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2 and 1
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3 and 2
A
Correct answer
Explanation
$\hspace{2cm}C_1+C_2=0 \Rightarrow C_2=0 \\
\text{Substitute $C_1$ & $C_2$ in equation (i), we get}\\
\hspace{4cm}y=(0+0_x)e^{-x}=0 \\
And\hspace{2cm}y(0.5)=0$
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3 and - 2
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2 and - 3
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3 and 2
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-3 and - 2
A
Correct answer
Explanation
37x + 29y = 53...(i)29x + 37y =13...(ii)
Adding (i) and (ii), we get66x + 66y = 66$\Rightarrow$ x + y = 1 ... (iii)
Subtracting (ii) from (i), we get 8x - 8y = 40$\Rightarrow$ x- y = 5 ...(iv)
Adding (iii) and (iv), we get 2x = 6$\Rightarrow$x = 3.
Subtracting (iv) from (iii), we get 2y = -4$\Rightarrow$ y = - 2
Hence, the solution is x = 3 and y = -2.
B
Correct answer
Explanation
2x – y + 4 = 2 (0) – (3) + 4 = 0 – 3 + 4 = 1
A
Correct answer
Explanation
x + y – 3
= 1 + 2 – 3
= 3 – 3 = 0
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2x = y + 5
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y = 2x + 5
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2y = x + 5
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None of these
A
Correct answer
Explanation
Number of red chairs is 5 less than twice the number of yellow ones, 2x = y + 5
A
Correct answer
Explanation
x + 2y - 4
= (1) + 2(1) - 4
= 1 + 2 - 4
= - 1