已知向量a=(sino,1),b=(1,coso),-π/2<o<π/2,(1)若a⊥b,求:o (2)求绝对值(a+b)的最大值?

问题描述:

已知向量a=(sino,1),b=(1,coso),-π/2<o<π/2,(1)若a⊥b,求:o (2)求绝对值(a+b)的最大值?

由已知向量a=(sino,1),b=(1,coso),- π/2<o<π/2,(1)若a⊥b,那么,向量a ·b =sin o +cos o =0 ,sin o =-cos o ,因为sin ²o +cos ²o =2sin ²o =1解得sin o =-√2/2,cos o =√2/2即o =-π/4或sin...