Pregunta: Example 3.3:vec(r)(θ)=a cos(θ)vec(e1)+asin(θ)vec(e2),a≠0-∞<θ<∞(i) Show that vec(r)(θ) is a regular parametric representation of a circle with radius a(ii) Discuss the multiple point(s)(iii) When this vector function be 1-1 ?

Example $3\mathrm{.}3$:

vec$(r)(\theta )=$a $cos(\theta )vec(e_1)+$asin$(\theta )vec(e_2),a\ne 0$

$-\infty <\theta <\infty$

$($i$)$ Show that vec$(r)(\theta )$ is a regular parametric representation of a circle with radius $a$

$($ii$)$ Discuss the multiple point$($s$)$

$($iii$)$ When this vector function be $1-1?$