मराठी

Find the equation of a straight line on which length of perpendicular from the origin is four units and the line makes an angle of 120° with the positive direction of x-axis.

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प्रश्न

Find the equation of a straight line on which length of perpendicular from the origin is four units and the line makes an angle of 120° with the positive direction of x-axis.

बेरीज
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उत्तर

Given that: OM = 4 units

∠BAX = 120°

∴ ∠BAO = 180° – 120° or ∠MAO = 60°

∠MOA + MAO = 90°    ......[∵ OM ⊥ AB]

θ + 60° = 90°

∴ θ = 30°

So, equation of AB in its normal form

x cos θ + y sin θ = p

⇒ x cos 30° + y sin 30° = 4

⇒ `x xx sqrt(3)/4 + y xx 1/2` = 4

⇒ `sqrt(3)x + y` = 8

Hence, the required equation is `sqrt(3)x + y` = 8

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पाठ 10: Straight Lines - Exercise [पृष्ठ १७८]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
पाठ 10 Straight Lines
Exercise | Q 11 | पृष्ठ १७८

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