Question
Mathematics Question on Geometric Progression
If A→=i^+2j→+3k^,B→=−i^+2j^+k^,C→=3i^+j and A→+1B→ is perpendicular to C→, thent is equal to
A
(A) -5
B
(B) 4
C
(C) 5
D
(D) -4
Answer
(C) 5
Explanation
Solution
Explanation:
Now,A→+tB→=(1−t)i^+(2+2t)j^+(3+t)k^(A→+tB→)⋅C→=3(1−t)+2+2t=0⇒−3t+2t+3+2=0⇒−t=−5⇒t=5