i think i get this now but just checking as i have the exam tomorrow and wont do this part if im getting it wrong.(adsbygoogle = window.adsbygoogle || []).push({});

(2) (a) find a vector perpendicular to a=i+2j-2k and b=-2i+3j+5k

just use the cross product? and get 15i+j+7k

(b) (i) find the equation of the plane through position vector (2,1,1) and perpendicular to the vector(3,-1,2)

is this Plane II=T(3,-1,2) + (2,1,1)

determin the perpendicular distance of plane II from the orogin

no idea here??

(ii) Find the equation of the plane III through three points (2,-2,1)=a (4,-1,6)=b and (3,-3,2)=c i use a-b and a-c and then do the cross product of these two answers to get (6i,-3j,-3k) am i right in thinking that it doesnt matter which 2 i use to get this cross product e.g i could use b-c b-a etc to find the normal then i have the answer planeIII=T(6,-3,-3)+(2,-2,1) (plus any point)

(iii) find the angles between the 2 planes, i'll wait for some feedback before i attempt this, thanks

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# Homework Help: Vector calculus answer check

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