Lakshya Education MCQs

Question:  expand and simplify (x + y)³
Options:
A.x³ - y³
B.x³ + y³
C.x³ + 3xy(x - y) + y³
D.x³ + 3xy(x + y) + y³
Answer: Option D
Explanation :

Submit Answer & Explaination

Earn Reward Points by submitting Detailed Explaination for this Question

More Questions on This Topic :

Question 1.  (a - b)² =
  1.    a² + b²
  2.    a² - b²
  3.    a² + 2ab + b²
  4.    a² - 2ab + b²
Answer: Option D
Explanation :
Question 2.  which of the following statements is false ?
  1.    If R is relexive, then R ∩ R-1 ≠ φ
  2.    R ∩ R-1 ≠ φ   =>R  is anti-symmetric.
  3.    If R, R' are relexive relations in A, then R - R' is reflexive
  4.    If R, R' are equivalence relations in a set A, then  R ∩ R'  is also an equivalence relation in A
Answer: Option C
Explanation :
Question 3.  if r = {(1, 2),(2, 3),(3, 3)} be a relation defined on a= {1, 2, 3} then r . r (= r2) is
  1.    {(1, 2),(1, 3),(3, 3)}
  2.    {(1, 3),(2, 3),(3, 3)}
  3.    {(2, 1),(1, 3),(2, 3)}
  4.    R itself
Answer: Option B
Explanation :
Question 4.  simplify (x - 9)(x + 10) ⁄ (x² - 81)
  1.    (x + 10) ⁄ (x - 9)
  2.    (x + 10) ⁄ (x + 9)
  3.    (x² + x - 90) ⁄ (x² - 81)
  4.    None of above
Answer: Option B
Explanation :
Question 5.  factorise -20x² - 9x + 20
  1.    (5 - 4x)(4 - 5x)
  2.    (5 - 4x)(4 + 5x)
  3.    (5 + 4x)(4 - 5x)
  4.    (5 + 4x)(4 + 5x)
Answer: Option C
Explanation :
Question 6.  factorise x² + x - 72
  1.    (x + 8)(x - 9)
  2.    (x - 8)(x + 9)
  3.    (x - ?72)²
  4.    (x - ?72)(x + ?72)
Answer: Option B
Explanation :

Check all Questions in this Topic : Click HERE