(i)Fourier sine transform off(x)fs(ω)=π2∫−∞∞f(x)sin(ωx)dx=π2∫010x2sin(ωx)dx+π2∫10∞0×sin(ωx)dx=ω1π2∫010x2d(−cos(ωx))=πω22(−x2cos(ωx)∣010+2∫010xcos(ωx)dx)=πω22(−100cos(100ω)+ω2∫010xd(sin(ωx)))=πω22(−100cos(100ω)+ω2xsin(ωx)∣010−ω2∫010sin(ωx)dx)=πω22(−100cos(100ω)+ω2xsin(ωx)∣010+ω22cos(ωx)∣010)=πω22(−100cos(100ω)+ω20sin(20ω)+ω22(cos(10ω)−1))Fourier cosine transform off(x)fc(ω)=π2∫−∞∞f(x)cos(ωx)dx=π2∫010x2cos(ωx)dx+π2∫10∞0×cos(ωx)dx=ω1π2∫010x2d(sin(ωx))=πω22(x2sin(ωx)∣010−2∫010xsin(ωx)dx)=πω22(100sin(100ω)+ω2∫010xd(cos(ωx)))=πω22(100sin(100ω)+ω2xcos(ωx)∣010−ω2∫010cos(ωx)dx)=πω22(100sin(100ω)+ω2xcos(ωx)∣010−ω22sin(ωx)∣010)=πω22(100sin(100ω)+ω20cos(20ω)−ω22sin(10ω))(ii)Fourier sine transform off(x)fc(ω)=π2∫−∞∞f(x)cos(ωx)dx=π2∫01xcos(ωx)dx+π2∫12(x+1)cos(ωx)dx+π2∫2∞0×cos(ωx)dx=ω1π2(∫01xd(sin(ωx))+∫12(x+1)d(sin(ωx)))=ω1π2(xsin(ωx)∣01−∫01sin(ωx)dx+(x+1)sin(ωx)∣12−∫12sin(ωx)dx)=ω1π2(sin(ω)+ωcos(ωx)∣01+3sin(2ω)−2sin(ω)+ωcos(ωx)∣12)=ω1π2(sin(ω)+ωcos(ω)−ω1+3sin(2ω)−2sin(ω)+ωcos(2ω)−cos(ω))=ω1π2(−sin(ω)+3sin(2ω)+ωcos(2ω)−ω1)Fourier cosine transform off(x)fc(ω)=π2∫−∞∞f(x)cos(ωx)dx=π2∫01xcos(ωx)dx+π2∫12(x+1)cos(ωx)dx+π2∫2∞0×cos(ωx)dx=ω1π2(∫01xd(sin(ωx))+∫12(x+1)d(sin(ωx)))=ω1π2(xsin(ωx)∣01−∫01sin(ωx)dx+∫(x+1)sin(ωx)∣12−∫12sin(ωx)dx)=ω1π2(sin(ω)+cos(ωx)∣01+3sin(2ω)−2sin(ω)+cos(ωx)∣12)=ω1π2(sin(ω)+cos(ω)−1+3sin(2ω)−2sin(ω)+cos(2ω)−cos(ω))=ω1π2(−sin(ω)+3sin(2ω)+cos(2ω)−1)fs(ω)=π2∫−∞∞f(x)sin(ωx)dx=π2∫01xsin(ωx)dx+π2∫12(x+1)sin(ωx)dx+π2∫2∞0×sin(ωx)dx=ω1π2(∫01xd(−cos(ωx))+∫12(x+1)d(−cos(ωx)))=ω1π2(−xcos(ωx)∣01+∫01cos(ωx)dx−(x+1)cos(ωx)∣12+∫12cos(ωx)dx)=ω1π2(−cos(ω)+ωsin(ωx)∣01−3cos(2ω)+2cos(ω)+ωsin(ωx)∣12)=ω1π2(−cos(ω)+ωsin(ω)−3cos(2ω)+2cos(ω)+ωsin(2ω)−ωsin(ω))=ω1π2(cos(ω)−3cos(2ω)+ωsin(2ω))
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