Find the product (( vec{a}+ vec{b}).(7 vec{a}-6 vec{b}) ).

1.	Find the product (( vec{a}+ vec{b}).(7 vec{a}-6 vec{b}) ).
A.	(2\| vec{a}\|^2+6 vec{a}. vec{b}-3\| vec{b}\|^2 )
B.	(8\| vec{a}\|^2+5 vec{a}. vec{b}-5\| vec{b}\|^2 )
C.	(2\| vec{a}\|^2+6 vec{a}. vec{b}-8\| vec{b}\|^2 )
D.	(7\| vec{a}\|^2+ vec{a}. vec{b}-6\| vec{b}\|^2 )
Answer» E.

Discussion

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