[填空题]
Ali is swimming in a public poolyy 52/kzgwa41fmonf9 q d:-l l with some of his friem c 1.puhyr) bxcl jui2+6o37bnds. At time t seconds, he encounters some waves withc1ybmlo ir3 up)2j+xh.b6cu7 height
$h_1$(t)=0.15sin(3t) from big Bobby jumping into the pool, and waves of height
$h_2$(t)=0.08sin(3t+1.25) from small Suzie jumping into the pool. Both
$h_1$(t) and $h_2$ (t) are measured in metres.
1.Write, in the form h(t)=Asin(ωt+φ), an expression for the total height of the waves Ali encounters at time t seconds.
2.Find the times in the first 5 seconds when Ali isn't affected by any waves.
3.Find the first time when the waves reaching Ali has maximum height.
Hence the first time when the wave reaching Ali has max height is at s
