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Question
Assertion (A): If 8 < 5(x + 1) – 2 ≤ 18, x ∈ R, then the smallest integer value of x is 0.
Reason (R): Multiplying each side of an inequation by the same integer does not change the inequality.
Options
A is true, R is false
A is false, R is true
Both A and R are true
Both A and R are false
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Solution
Both A and R are false
Explanation:
Given,
⇒ 8 < 5(x + 1) – 2 ≤ 18
Solving L.H.S of inequation,
⇒ 8 < 5(x + 1) – 2
⇒ 5(x + 1) – 2 > 8
⇒ 5x + 5 – 2 > 8
⇒ 5x + 3 > 8
⇒ 5x > 8 – 3
⇒ 5x > 5
⇒ `x > 5/5`
⇒ x > 1 ...(1)
Solving R.H.S of inequation,
⇒ 5(x + 1) – 2 ≤ 18
⇒ 5x + 5 – 2 ≤ 18
⇒ 5x + 3 ≤ 18
⇒ 5x ≤ 18 – 3
⇒ 5x ≤ 15
⇒ `x ≤ 15/5`
⇒ x ≤ 3 ...(2)
From (1) and (2), we get :
⇒ 1 < x ≤ 3, x ∈ R
∴ The smallest integer value of x is 2.
∴ Assertion (A) is false.
Multiplying each side of an inequation by the same positive integer does not change inequality, while the inequality changes if multiplied by negative integer.
∴ Reason (R) is false.
Hence, Both A and R are false.
