Mathematics · Quantitative Aptitude
Algebraic Expressions and Polynomials
292 Questions
Algebraic expressions and polynomials form the foundation of algebra, involving variables, constants, and mathematical operations. This topic is heavily tested in the quantitative aptitude sections of SSC, banking, and state exams. Use these questions to practice expanding, factoring, and simplifying various polynomial expressions.
Expanding algebraic expressionsFactoring polynomialsAlgebraic identitiesFinding common factorsSimplifying numerical statements
Algebraic Expressions and Polynomials Questions
Find the common factors of the given terms:
$2x, 3x^2, 4$
D
Correct answer
Explanation
$2x$, $3x^2$, $4$
The factors of $2x=2\times x$
The factors of $3x^2=3\times x\times x$
The factors of $4=2\times 2$
Thus, the common factors is $1$
Find the common factors of the given terms:
$2y, 22xy$
A
Correct answer
Explanation
$2y$,$22xy$
The factors of $2y=2\times y$
The factors of $22xy=2\times 11\times x\times y$
Thus, the common factors are $2\times y=2y$
Find the common factors of the given terms:
$16 x^3, 4x^2, 32x$
C
Correct answer
Explanation
$16 x^3$, $4x^2$, $32x$
The factors of $16 x^3=2\times 2\times 2\times 2\times x\times x\times x$
The factors of $4x^2=2\times 2 \times x\times x$
The factors of $32x=2\times 2\times 2\times 2\times 2\times x$
The common factors are $2\times 2 \times x=4x$
What is correction factor(C.F) in the rank correlation coefficient.
-
C.F $=\sum (m^{2}-1)$
-
C.F $=\sum (m^{2}+1)$
-
C.F $=\sum m^{2}(m^{2}-1)$
-
C.F $=\sum m(m^{2}-1)$
D
Correct answer
Explanation
The correction factor in the rank correlation coefficient is given by $\sum m(m^2-1)$
where $m$ is the number of times the data repeats.
Hence, C.F $=\sum m(m^2-1)$.
The normal form of $2x-2y+z=5$ is
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$12x-4y+3z=39$
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<p class="MsoNormal">$\displaystyle \dfrac{-6}{7}x+\dfrac{2}{7}y+\dfrac{3}{7}z=1$</p>
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<p class="MsoNormal">$\displaystyle \dfrac{12}{13}x-\dfrac{-4}{13}y+\dfrac{3}{13}z=3$</p>
-
<p class="MsoNormal">$\displaystyle \dfrac{2}{3}x-\dfrac{2}{3}y+\dfrac{1}{3}z=\dfrac{5}{3}$</p>
D
Correct answer
Explanation
The dr's of the normal to the plane are $(2,-2,1)$.
The dc's will be $\left ( \dfrac{2}{3} , \dfrac{-2}{3} , \dfrac{1}{3} \right)$
Hence, the equation of the plane in the normal form will be,
$ \dfrac{2x}{3} - \dfrac{2y}{3} + \dfrac{z}{3} $ = $ \dfrac{5}{3} $
Use the BODMAS rule to reduce the expression: $x-1[(x^2+x-2)(x^2-1^2)\div (x-1)^2]$.
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$x^3+2x^2-x-2$
-
$x^3-2x^2-x-2$
-
$-x^3+2x^2-x-2$
-
$x^3+2x^2+x-+$
A
Correct answer
Explanation
$x-1[(x^2+x-2)(x^2-1^2)\div (x-1)^2]$
We need to follow BODMAS rule.
=> Brackets (parts of a calculation inside brackets always come first).
=> Orders (numbers involving powers or square roots).
=> Division.
=> Multiplication.
=> Addition.
=> Subtraction.
$=$ $\frac{x-1(x^2+x-2)(x+1)(x-1)}{(x-1(x-1)}$
$=$ $x^3+x^2-2x+x^2+x-2$
$=$ $x^3+2x^2-x-2$
Expand the expression using BODMAS rule: $x^2-x[(-x)(-2+x)]\div x+x^3-3x^2$
-
$x^3-x^2-2x$
-
$-x^3-x^2-2x$
-
$x^3-x^2+2x$
-
$x^3+x^2+2x$
A
Correct answer
Explanation
$x^2-x[(-x)(-2+x)]\div x+x^3-3x^2$
We need to follow BODMAS rule.
=> Brackets (parts of a calculation inside brackets always come first).
=> Orders (numbers involving powers or square roots).
=> Division.
=> Multiplication.
=> Addition.
=> Subtraction.
$=$ $-2x^2-x[\dfrac{(-x)(-2+x)}{x}]+x^3$
$=$ $-2x^2-x[2-x]+x^3$
$=$ $x^3-2x^2-2x+x^2$
$=$ $x^3-x^2-2x$
Reduce the following expression using BODMAS rule: $2y-1(y-y^2)+5y[(-2y)(y^2-1)]$
-
$10y^4+11y^2+y$
-
$-10y^4+11y^2-y$
-
$-10y^4+11y^2+y$
-
$-10y^4-11y^2+y$
C
Correct answer
Explanation
$2y-1(y-y^2)+5y[(-2y)(y^2-1)]$
We need to follow BODMAS rule.
=> Brackets (parts of a calculation inside brackets always come first).
=> Orders (numbers involving powers or square roots).
=> Division.
=> Multiplication.
=> Addition.
=> Subtraction.
$=$ $2y-y+y^2+5y[-2y^3+2y]$
$=$ $y+y^2-10y^4+10y^2$
$=$ $-10y^4+11y^2+y$
$24[x+1]-[x^2-24+x]-[2x^2]\div [x^2]$ using BODMAS rule to reduce the expression.
-
$x^2+23x+46$
-
$-x^2+23x+46$
-
$-x^2-23x+46$
-
$-x^2+23x-46$
B
Correct answer
Explanation
$24[x+1]-[x^2-24+x]-[2x^2]\div [x^2]$
We need to follow BODMAS rule.
=> Brackets (parts of a calculation inside brackets always come first).
=> Orders (numbers involving powers or square roots).
=> Division.
=> Multiplication.
=> Addition.
=> Subtraction.
$=$ $24[x+1]-[x^2-24+x]-[2x^2]\div [x^2]$
$=$ $24x+24-x^2+24-x-2$
$=$ $-x^2+46+23x$
$=$ $-x^2+23x+46$
Solve the expression using BODMAS rule: $3x(x-2)+x(x^2\times 2x)-12x$
-
$2x^5-3x^2-18x$
-
$2x^5+3x^2-18x$
-
$2x^5+3x^2+18x$
-
$-2x^5-3x^2-18x$
B
Correct answer
Explanation
$3x(x-2)+x(x^2\times 2x)-12x$
We need to follow BODMAS rule.
=> Brackets (parts of a calculation inside brackets always come first).
=> Orders (numbers involving powers or square roots).
=> Division.
=> Multiplication.
=> Addition.
=> Subtraction.
$=$ $3x(x-2)+x(x^2\times 2x)-12x$
$=$ $3x^2-6x+x^3\times2x^2-12x$
$=$ $3x^2-6x+2x^5-12x$
$=$ $2x^5+3x^2-18x$
After applying invertendo to $3:7::2:9$ we get
-
$3:7::2:9$
-
$3:2::7:9$
-
$9:7::2:3$
-
$7:3::9:2$
D
Correct answer
Explanation
If $a : b :: c : d$ then $b : a :: d : c$ is invertendo property of ratios
We have $3:7::2:9$
After applying invertendo we get
$7:3::9:2$
Option D is correct
Find the value of $a$ and $b$ respectively
After applying invertendo to $2:5::3:9$ we get $a:2::9:b$
-
$9$ and $2$
-
$2$ and $9$
-
$3$ and $5$
-
$5$ and $3$
D
Correct answer
Explanation
If $a : b :: c : d$ then $b : a :: d : c$ is invertendo property of ratios
We have $2:5::3:9$
After applying invertendo we get
$5:2::9:3\equiv a:2::9:b$
$\Rightarrow a=5,b=3$
Option D is correct
After applying invertendo to $1:2::3:4$ we get
-
$1:2::3:4$
-
$2:1::4:3$
-
$1:3::2:4$
-
$4:2::3:1$
B
Correct answer
Explanation
If $a : b :: c : d$ then $b : a :: d : c$ is invertendo property of ratios
We have $1:2::3:4$
After applying invertendo we get
$2:1::4:3$
Option B is correct
After applying invertendo to $1:2::8:9$ we get:
-
$2:1::9:8$
-
$1:8::2:9$
-
$8:9::1:2$
-
$1:9::8:2$
A
Correct answer
Explanation
If $a : b :: c : d$ then $b : a :: d : c$ is invertendo property of ratios
We have $1:2::8:9$
After applying invertendo we get
$2:1::9:8$
Option A is correct
$(1-\omega +\omega^{2})(1-\omega^{2}+\omega^{4})(1-\omega^{4}+\omega^{8})......$to 2n factors =
-
2
-
$2^{2n}$
-
2n
-
none of these
B
Correct answer
Explanation
Given,
$(1−ω+ω^2)(1−ω^2+ω^4)(1−ω^4+ω^8)$...... to $2n$
we have,
$1+w+w^2=0$
and $w^3=1$
$\Rightarrow (-w-w)(-w^2-w^2)(-w-w)....................2n$
$=(-2w)(-2w^2)(-2w).............2n$
here, we can see, 2 consecutive terms are same and are even, so we get,
$=(4w^3)(4w^3)(4w^3).........2n$
$=4 \times 4 \times .........2n$
$=2^2.........2n$
for $2n$ terms, we get,
$=2^{2n}$