Help with two questions please,
1)Two forces act as a point in the plane. The angle between the two forces is given. Find the magnitude of the resultant force. Forces of 40.1 and 30.5 lb, forming an angle of 24.5 degrees ( round to the nearest pound)
2)1)Find the dot product of i+4j and 7i-j (would this be 0? or 3? )

Question

Help with two questions please,
1)Two forces act as a point in the plane. The angle between the two forces is given. Find the magnitude of the resultant force. Forces of 40.1 and 30.5 lb, forming an angle of 24.5 degrees ( round to the nearest pound)
2)1)Find the dot product of i+4j and 7i-j (would this be 0? or 3? )

amistre64 · Answer

inner product of vector is the product of their like parts, added

 (a,b)
.(x,y)
-----
ax+by

amistre64 · Answer

the resultant of 2 vectors is just the sum of their like parts

    k(a,b)
+  j(x,y)
----------
(ka+jx, kb+jy)

the magnitude is the length of that vector

amistre64 · Answer

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anonymous · Answer

for 1) would it be then 181 lb then?

amistre64 · Answer

i wouldnt know off hand ...

amistre64 · Answer

Forces of 40.1 and 30.5 lb, forming an angle of 24.5 

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