f(x)=Asin(wx+q) qE(-π/2 π/2) (A>0 W>0) 图像经过(0 1)1 求函数的解析式
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f(x)=Asin(wx+q) qE(-π/2 π/2) (A>0 W>0) 图像经过(0 1)1 求函数的解析式,2 将函数y=f(x)的图像向右平移π/4个单位,得到函数y=g(x)的图像,求y=g(x)的最大值,并求出此时自变量的取值集合.

有四个点(-π/12,0),(0,1),(5π/12,0),(11π/12,0)

(1)解析:∵f(x)=Asin(wx+q) qE(-π/2 π/2) (A>0 W>0) 图像经过(0,1)

f(0)=Asin(q)=1

∵函数图像过(-π/12,0),(0,1),(5π/12,0)

∴T/2=5π/12-(-π/12)= π/2==>T=π==>w=2π/π=2

∴f(-π/12)=Asin(-π/6+q)=0==>sin(-π/6+q)=0==>q=π/6

∴A/2=1==>A=2

∴f(x)=2sin(2x+π/6)

(2)解析:g(x)= 2sin(2(x-π/4)+π/6)=2sin(2x-π/3)

最大值为2,此时2x-π/3=2kπ+π/2==>x=kπ+5π/12