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Need solution to this

Need solution to this-example-1

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Let's first understand what's relative here, it refers to Point of reference , the point, in respect to which other's position are to be considered, which here is O, the Origin with coordinates (0,0) as we are talking about two-dimensional reference frame. What position vector means? Say, we have the point of Reference X, and we've the position vector of Y with respect to X, then it can be written as
{\overrightarrow{XY}}. Now, using this simple rule we can have,


  • {\overrightarrow{OA}=-2\hat{i}+7\hat{j}}

  • {\overrightarrow{OB}=2\hat{i}-\hat{j}}

  • {\overrightarrow{OC}=6\hat{i}+\lambda \hat{j}}

Now, let's calculate
{\overrightarrow{AC}} firstly;


{:\implies \overrightarrow{AC}=\overrightarrow{OC}-\overrightarrow{OA}}


{:\implies \overrightarrow{AC}=8\hat{i}+(\lambda -7)\hat{j}}

Now, here
{AC} just means the the magnitude of the vector [tex{\overrightarow{AC}}[/tex], and we're aware that magnitude of a vector
{\overrightarrow{X}=x\hat{i}+y\hat{j}} is given by,
{X=\sqrt{x^(2)+y^(2)}}, so according to question;


{:\implies \sqrt{64+(\lambda -7)^(2)}=17}

Squaring both sides;


{:\implies (\lambda -7)^(2)=289-64=225}


{:\implies \lambda -7=\pm 15}


{:\implies \boxed{\underline{\bf{\lambda =22,\:or\:-8}}}}

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