- #1

HF08

- 39

- 0

**a,b**[tex]\in[/tex]

**R**[tex]^{m}[/tex],

**b**[tex]\neq[/tex]

**0**and set [tex]\phi[/tex](t)=

**a**+t

**b**.

We must show that the angle between [tex]\phi[/tex](t[tex]_{1}[/tex])-[tex]\phi[/tex](t[tex]_{0}[/tex]) and [tex]\phi[/tex](t[tex]_{2}[/tex])-[tex]\phi[/tex](t[tex]_{0}[/tex])

is 0 or [tex]\pi[/tex] for any t[tex]_{0}[/tex],t[tex]_{1}[/tex],t[tex]_{2}[/tex],[tex]\in[/tex]

**R**with t[tex]_{1}[/tex],t[tex]_{2}[/tex][tex]\neq[/tex].

The 0,1, and 2 are supposed to be subscripts next to t, but my Latex is showing is as superscripts? I don't know why.

Here is my work:

I don't know where to start. My guess is we start with [tex]\phi[/tex](t)=

**a**+t

**b**. Do we use the law of cosines? How can I even begin to show what looks like arbitrary definitions, arbitrary values and show either 0 or [tex]\pi[/tex]? Please

help me. It isn't lack of trying, I need to attack this problem, but I feel more like I am drowning.

Thank You,

HF08