Question

in a plane triangle find the maximum value of cos a cos b cos c​

Answer 1

we know from right triangle,

since,

cos = y/r {y = perpendicular and r = hypotenuse

so, and x= base}

from plane triangle,

{by considering AB = 9, BC=3,

AC=8}

Therefore,

cos a = y/r

= 3/8

cos b = y/r

= 9/3

cos c = y/r

= 9/8