已知函数∫(x)=3sin(2x-π/3),g(x)=4sin(2x+π/3)则函数∫(x)+g(x)的振幅A的值为 A √13 B 5C 7 D 13

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已知函数∫(x)=3sin(2x-π/3),g(x)=4sin(2x+π/3)则函数∫(x)+g(x)的振幅A的值为A√13B5C7D13已知函数∫(x)=3sin(2x-π/3),g(x)=4sin

已知函数∫(x)=3sin(2x-π/3),g(x)=4sin(2x+π/3)则函数∫(x)+g(x)的振幅A的值为 A √13 B 5C 7 D 13
已知函数∫(x)=3sin(2x-π/3),g(x)=4sin(2x+π/3)则函数∫(x)+g(x)的振幅A的值为 A √13 B 5
C 7 D 13

已知函数∫(x)=3sin(2x-π/3),g(x)=4sin(2x+π/3)则函数∫(x)+g(x)的振幅A的值为 A √13 B 5C 7 D 13
函数f(x)=3sin(2x-π/3),g(x)=4sin(2x+π/3),
则f(x)+g(x)=3sin(2x-π/3)+4sin(2x+π/3)
=3sin2xcosπ/3-3cos2xsinπ/3+4sin2xcoπ/3+4cos2xsinπ/3
=(3/2+2)sin2x+(2√ 3-(3√ 3)/2)cos2x
=(7/2)sin2x+(1/2)√ 3cos2x
∴∫(x)+g(x)的振幅A=√{(7/2)²+[(1/2)√ 3]²}=√ 13