Question

r and r ' denote angle inside an equilateral prism as usual, in degrees. Consider that during some time interval from $t=0$ to $t=t$, r ' varies with time $r^{\prime }=10+t^2$, During this time r will vary as $x-t^2$ . Find x ?

Answer 1

Let A be angle of prism

By properties of triangle $r+r^{\prime }=A$

=> $x-t^2+10+t^2=A$

=> $x=A-10$

Since it is equilateral prism, $A=60$

=> $x=60-10=50$