Question

two vectors have negative 3 unit and 4 m respectively what should be the angle between them

Answer 1

Howdy!!

your answer is ----

LET,vector A = 3 unit and vector B = 4unit

Given, their resultant is 1 unit .

alos, let angle between them is ∅

so √A^2+B^2+2ABcos∅ = 1

=> A^2+B^2+2ABcos∅ = 1

=> 3^2 + 4^2 + 2×3×4cos∅ = 1

=> 9+16+24cos∅ = 1

=> 25+24cos∅ = 1

=> cos∅ = -24/24

=> cos∅ = -1

=> cos∅ = cos180°. [ cos180° = -1 ]

=> ∅ = 180°

hence, angle between two vectors is 180°

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hope it help you

Answer 2

|a ⃗ | = 3m
 |b ⃗ | = 4 (
a) if R = 1 unit ⇒ √(3^2+4^2+2.3.4.cos⁡θ ) = 1 Θ = 180°
(b) √(3^2+4^(2 )+22.3.4.cos⁡θ ) = 5 Θ = 90°
 (c) √(3^2+4^2+2.3.4.cos⁡θ ) = 7 θ = 0°
Therefore the Angle between them is 0°
Hope it helps