Misc 3 - Chapter 5 Class 11 Linear Inequalities
Last updated at April 16, 2024 by Teachoo
Solving inequality (both sides)
Last updated at April 16, 2024 by Teachoo
Misc 3 Solve the inequality -3 ≤ 4 − 7𝑥2 ≤ 18 -3 ≤ 4 − 7𝑥2 ≤ 18 Subtracting 4 all sides (Eliminating 4) -3 – 4 ≤ 4 − 7𝑥2 – 4 ≤ 18 – 4 -7 ≤ − 7𝑥2 ≤ 14 Multiplying 2 all sides (Eliminating 2) -7 × 2 ≤ − 7𝑥2 × 2 ≤ 14 × 2 -14 ≤ −7𝑥 ≤ 28 Dividing 7 all sides (Eliminating 7) −14 7 ≤ −7𝑥 7 ≤ 28 7 −2 ≤−𝑥 ≤ 4 Since x is negative, we multiply both sides by -1 & change the signs (– 1) × (-2) ≥ (–1) × (–x) ≥ (–1) × (4) 2 ≥ x ≥ −4 −4 ≤ x ≤ 2 Thus, x is a real number which is less than or equal to 2 and greater than or equal to −4 Hence, x ∈ [−𝟒, 2] is the solution