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Operations on Algebraic Expressions — MATHS STD 8 — Question

Gujarat BoardEnglish MediumSTD 8MATHSOperations on Algebraic Expressions1 Mark
MCQ
Assertion (A): $\left(\frac{1}{x+y}\right)\left(\frac{1}{x-y}\right)=\frac{1}{x^2}-\frac{1}{y^2}$.
Reason (R): $(a+b)(a-b)=a^2-b^2$.
  • A
    Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
  • B
    Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of Assertion (A).
  • C
    Assertion (A) is true but Reason (R) is false.
  • ✓
    Assertion (A) is false but Reason (R) is true.
✓

Answer

Correct option: D.
Assertion (A) is false but Reason (R) is true.
(D) Assertion (A) is false but Reason (R) is true.
$\left(\frac{1}{x+y}\right)\left(\frac{1}{x-y}\right)=\frac{1}{(x+y)(x-y)}=\frac{1}{\left(x^2-y^2\right)}$

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