已知函数f(x)=2sin(1/3x-π/6),x∈R (1)求f(0)的值;(2)设α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+π/2)=6/5.求sin(α+β)的值.

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已知函数f(x)=2sin(1/3x-π/6),x∈R (1)求f(0)的值;(2)设α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+π/2)=6/5.求sin(α+β)的值.

已知函数f(x)=2sin(1/3x-π/6),x∈R (1)求f(0)的值;(2)设α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+π/2)=6/5.求sin(α+β)的值.
已知函数f(x)=2sin(1/3x-π/6),x∈R (1)求f(0)的值;
(2)设α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+π/2)=6/5.求sin(α+β)的值.

已知函数f(x)=2sin(1/3x-π/6),x∈R (1)求f(0)的值;(2)设α,β∈[0,π/2],f(3α+π/2)=10/13,f(3β+π/2)=6/5.求sin(α+β)的值.
1.f(0)=2sin(-π/6)=2×(-1/2)=-1
2.f(3α+π/2)=2sin[1/3(3α+π/2)-π/6]=2sinα=10/13 sinα=5/13 α∈[0,π/2] cosα=12/13
f(3β+π/2)=2sin[1/3(3β+π/2)-π/6]=2sinβ=6/5 sinβ=3/5 β∈[0,π/2] cosβ=4/5
sin(α+β)=sinαcosβ+sinβcosα=5/13×4/5+12/13×3/5=56/65

上菁优网。以下是这题的答案网址,直接点击打开就有,有详细答案过程、考点,这题是2011年广东高考题。
http://m.jyeoo.com/math2/ques/detail/5ecd8e18-3aa4-4222-8c50-7f5bc4e260d1

f(3a+π/2)=2sin(1/3(3a+π/2)-π/6)=2sina=10/13,sina=5/13,cosa=12/13
f(3b+2π)=2sin(1/3(3b+2π)-π/6)=2cosb=6/5, cosb=3/5,sinb=4/5
cos(a+b)=cosa*cosb-sina*ainb=12/13*3/5-5/13*4/5=16/65
sin(α+β)=sinαcosβ+sinβcosα=5/13×4/5+12/13×3/5=56/65