# Math Help - in a triangle

1. ## in a triangle

1) if in a triangle ABC <A = 60○,then $(1+\frac{a}{c}+\frac{b}{c} )(1+\frac{c}{b}-\frac{a}{b})$ equals ??
2)in any triangle ABC least value of R/s

where R-ortho centre and s-semi perimeter

2. $(1 + \frac{a}{c} + \frac{b}{c})(1 + \frac{c}{b} - \frac{a}{b}) = \frac{( b + c + a)(b + c - a)}{bc} = \frac{(b + c)^2 - a^2}{bc}$

Using the cosine rule, substitue the value of a^2 and simplify.