→n=∣∣
∣
∣∣^i^j^k11001−1∣∣
∣
∣∣
→n=−^i+^j+^k
Equation of plane P is
⇒−1(x−1)+1(y−0)+1(z−0)=0
⇒x−y−z−1=0
If Q(α,β,γ) is the foot of the perpendicular drawn from the point M(1,0,1) on the plane P, then
α−11=β−0−1=γ−1−1=−(1−0−1−1)3
∴α=43,β=−13,γ=23
⇒(α+β+γ)=53
∴3(α+β+γ)=5