pls solve it Q If a→,b→,c→ are three non-zero vectors , no too - Maths - Vector Algebra

Question

pls solve it

Q If a → , b → , c → are three non-zero vectors , no
too of which are collinear & the vector a → + b → is
collinear with c → ,   b → + c → is collinear
with a → then a → + b → + c → is equal to -

a) a → (b) b → (c) c → (d) 0

Neha Sethi · Accepted Answer

Dear student
It is given thata→+b→ is collinear with c→⇒a→+b→=λ1c→ for some scalar λ1     
(1)and b→+c→ is collinear with a→⇒b→+c→=λ2a→ for some scalar λ2     
(2)From (1), we havea→=λ1c→-b→Substituting this value in (ii), we get1+λ2b→+(1-λ1λ2)c→=0→⇒1+λ2=0 and 1-λ1λ2=0     As b→ and c→ are collinear⇒λ2=-1 and λ1=-1Putting the value of λ1 and λ2 in (1) and (2) resp, we geta→+b→=-c→ and a→+b→+c→=0→
Regards

pls solve it... Q. If a → , b → , c → are three non-zero vectors , no. too of which are collinear & the vector a → + b → is collinear with c → , b → + c → is collinear with a → then a → + b → + c → is equal to - a) a → (b) b → (c) c → (d) 0