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Question : 11 of 100
Marks:
+1,
-0
Solution:
Since,
c is perpendicular to
a and
b.
So,c=λ(a×b) a=+− b=+2+ Now,
a×b=|| =(1+2)−(1+1)+(2−1) =3−2+ ⇒‌‌c=λ(3−2+) Now, c
⋅(++3)=8 λ(3−2+)(++3)=8 ⇒‌4λ=8 ∴‌λ=2 So,
c=2(3−2+) So,
c⋅(a×b)=2(3−2+)(3−2+) =2(9+4+1) =28
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