Question

向量垂直公式向量a=[2cos(-θ),2sin(-θ)],向量b=[cos(90°-θ),sin(90°-θ)]若存在

Answer 1

|a|=2,|b|=1,a*b=0

x⊥y => x*y=0 => -4k+t(t^2-3)=0

k=t(t^2-3)/4

=> （k+t^2)/t=(t^2+4t-3)/4 >= -7/4

当 t=-2,k=-1/2 时 取得最小值-7/4