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Vector O A , O B , O C are on the same plane, | O A |=1,| O B |=1,| O C |= 2 , the relative position is shown in the figure. If =7 and O B O C = 4 and O C =m O A +n O B ,(m, n R) , find the value of (m+n) .

Correct answer

3

Step-by-step solution

aligned O C & =m O A +n O B c & =m a +n b | a | & =1,| b |=1,| c |= 2 , =7 aligned Given Now take dot of equation (1) with a and c to get aligned m & =5 / 4 ; n=7 / 4 m+n & =3 aligned

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