MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Definition of Vector

If |a⃗ +b⃗|...

Question

If $| \to a + \to b | > | \to a - \to b |$ then the angle between $\to a$ and $\to b$ is

A

Acute

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

B

Obtuse

No worries! We‘ve got your back. Try BYJU‘S free classes today!

C

Right angle

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

None

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A Acute
$\begin{matrix} L e t t h e a n g l e b e t w e e n \to a a n d \to b b e θ {∣ ∣ ∣ \to a + \to b ∣ ∣ ∣}^{2} = {∣ ∣ \to a ∣ ∣}^{2} + {∣ ∣ ∣ \to b ∣ ∣ ∣}^{2} + 2 ∣ ∣ \to a ∣ ∣ ∣ ∣ ∣ \to b ∣ ∣ ∣ cos θ a n d {∣ ∣ ∣ \to a - \to b ∣ ∣ ∣}^{2} = {∣ ∣ \to a ∣ ∣}^{2} + {∣ ∣ ∣ \to b ∣ ∣ ∣}^{2} - 2 ∣ ∣ \to a ∣ ∣ ∣ ∣ ∣ \to b ∣ ∣ ∣ cos θ a c c o r d i n g t o q u e s t i o n ∣ ∣ ∣ \to a - \to b ∣ ∣ ∣ > ∣ ∣ ∣ \to a - \to b ∣ ∣ ∣ {∣ ∣ ∣ \to a - \to b ∣ ∣ ∣}^{2} > {∣ ∣ ∣ \to a - \to b ∣ ∣ ∣}^{2} ∴ 4 ∣ ∣ \to a ∣ ∣ ∣ ∣ ∣ \to b ∣ ∣ ∣ cos θ > 0 \Rightarrow cos θ > 0 ∴ θ \in [0, \frac{π}{2}] s o, t h e a n g l e i s a c u t e a n g l e H e n c e, t h e o p t i o n A i s t h e c o r r e c t a n s w e r . \end{matrix}$

Suggest Corrections

thumbs-up

0

Similar questions

| \to a + \to b | < | \to b - \to a |

then angle between

\to a

\to b

| \to A + \to B | = | \to A - \to B |

, then the angle between

\to A

\to B

| \to A + \to B | = | \to A | = | \to B |

, then the angle between

\to A

\to B

\to a

\to b

are unequal vectors such that

(\to a - \to b) \times [(\to b + \to a) \times (2 \to a + \to b)] = \to a + \to b

, then the angle

θ

\to a

\to b

| \to A | = | \to B |

, then what is the angle between

\to A + \to B

\to A - \to B

:

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Introduction

MATHEMATICS

Watch in App

explore_more_icon

Explore more

Definition of Vector

Standard XII Mathematics

Join BYJU'S Learning Program

CrossIcon