Question 1132778
{{{u}}}= <{{{2}}} ,{{{8}}}>, {{{v}}}=<{{{4}}} ,{{{-5}}}>

{{{proj[v]u=(u*v)/(abs(u))^2}}}*<{{{4}}} ,{{{-5}}}>


{{{u*v= 8 -40=-32}}}

{{{(abs(u))^2=(sqrt(4^2+5^2))^2=(sqrt(41))^2}}}


substitute in {{{proj[v]u=(u*v)/(abs(u))^2}}}*<{{{4}}} ,{{{-5}}}>


{{{proj[v]u}}}={{{-32/(sqrt(41))^2}}}*<{{{4}}} ,{{{-5}}}>


{{{proj[v]u}}}=({{{-32/41}}})*<{{{4 }}},{{{-5}}}>


proj[v]u=({{{-(32/41)*4}}},{{{-(32/41)(-5)}}})


{{{proj[v]u}}}=({{{-128/41}}} ,{{{160/41}}})