2026年8月国际A卷 · 第 19 题

The function \( f \) is defined by \( f\left(x\right)\ =\ a\left(2.7^x+2.7^b\right) \) , where a and b are integer constants and \( 0<a<b \) . The functions g and h are equivalent to function \( f \), where k and m are constants. Which of the following equations displays the y-coordinate of the y-intercept of the graph of \( y=f(x) \) in the xy-plane as a constant or coefficient?
I. \( g(x)=a(2.7^{x}+k) \) 
II.\( h(x)=a(2.7)^x+m \)