Question

if P=2i+j+k and Q=i-j+2k and R=I+2j+k find (P+Q)×(R+P).​

Answer 1

Answer:

P=2i+j+k

Q=i-j+2k

R=i+2j+k

To find (P+Q)×(R+P).​

Substituting value if P,Q and r

(P+Q)×(R+P)=(2i+j+k +i-j+2k) X (2i+j+k+i+2j+k )

(P+Q)×(R+P)=((3i + 3k)(3i + 3j + 2k )

(P+Q)×(R+P)=$3(i+k ) (3i + 3j +2k) \\3(3i^2 +3ij + 2ik + 3ik + 3jk + 2k^2)\\3(3i^2 +3ij + 5ik + 3jk + 2k^2)\\9i^2 + 9ij + 15 ik + 9jk + 6k^2$

(P+Q)×(R+P)=

Explanation: