Question

What is angle between P + q and P cross q

Answer 1

Answer:

θ = 90 °

Explanation:

Lets take

 =2i + 3 j

q= i + j

So

p+q= 2i + 3 j + i + j

p+q= 3i + 4 j

A= p+q= 3i + 4 j

p x q = (2i + 3 j)( i + j)

We know that

i x i = jx j= k x k =0

i x j = k  ,j x k = i  ,k  x i =j  

So

p x q = (2i + 3 j) x ( i + j) = 2 i x i + 3 j x  i +2 i x j + 3 j x j  = 0- 3 k + 2 k + 0

p x q = - k

B=p x q = - k

Lets take angle between p+ q and p x q is θ

$cos\theta =\dfrac{A.B}{|A||B|}$

We know that

i.i = j.j=k.k=1

i.j=j.k=k.i=0

$cos\theta =\dfrac{(3i + 4 j).(- k)}{|A||B|}$

So we can say that

$cos\theta =0$

So θ = 90 °

Answer 2

Explanation:

Hope.... This Explanatin is Help You......

Thank You.....

Lets Crack it