what will happen if we change carrier signal from sinusoidal to triangula in amplitude or frequency modulation

Answer 1

The bandwidth will increase since the carrier would now contain all the odd harmonics of the carrier. So if your carrier was F, you'd now be adding 3F, 5F etc with sidebands at each of these frequencies based on the modulating signal.

Answer 2

Nothing. The receiver is going to resonate in time with the frequency. Its own capacitiance and inductance will round of the corners of the wave form so that is resonating with a sinusoidal wave form even though it is excited by a saw tooth wave.