The scalar product of the vector a⃗ = î + ĵ + k̂ with a unit vector along the - Maths - Vector Algebra

Question

The scalar product of the vector a⃗ = î + ĵ +
k̂ with a unit vector along the sum of the vectors b⃗ =
2î + 4ĵ – 5k̂ and c⃗ = λî
+ 2ĵ + 5k̂ is equal to 1 Find the value of λ and
hence find the unit vector along b⃗ + c⃗ (All India
2019)

Sukhjinder Singh · Accepted Answer

The scalar product of the vector a⃗ = î + ĵ + k̂ with a unit vector along the sum of the vectors b⃗ = 2î + 4ĵ – 5k̂ and c⃗ = λî + 2ĵ + 5k̂ is equal to 1. Find the value of λ and hence find the unit vector along b⃗ + c⃗ . (All India 2019)