Start by letting h ( x ) = f ( x ) − x + 1 2 = g ( x ) + sin ( x ) − x + 1 2 {\displaystyle h(x)=f(x)-{\frac {x+1}{2}}=g(x)+\sin(x)-{\frac {x+1}{2}}} . Find two numbers c 1 {\displaystyle c_{1}} and c 2 {\displaystyle c_{2}} such that h ( c 1 ) > 0 {\displaystyle h(c_{1})>0} and h ( c 2 ) < 0 {\displaystyle h(c_{2})<0} . Which theorem can we use now?
