1611689564-c292adb9a0ffac330f3ca30cdb684bd6 (826864), страница 10
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fb(y)=− f (y)=−ie−(y +a )/2 sh ay .∨∨242. fb(y) =f (−y) = e−(y+a) /2 . 43. fb(y) = − f (y) = −i81/2 π −1/2 ay(y 2 +∨∨a2 )−2 . 44. fb(y) =f (y) = 81/2 π −1/2 y 2 (y 2 + 1)−2 . 45. fb(y) = − f (y) =2+a2 )/2∨i81/2 π −1/2 y(1−3y 2 )(y 2 +1)−3 . 46. fb(y) =f (−y) = 21/2 π −1/2 (1−y)−1 sin πy .∨∨47. fb(y) =f (y) = 21/2 π −1/2 y(1 − y 2 )−1 sin πy . 48. fb(y) = − f (y) =∨−i21/2 π −1/2 (1 − y 2 )−1 sin πy .
49. fb(y) =f (−y) = i(2π)−1/2 (1 − y)−1 (1 +∨∨e−iπy ). 50. fb(y) =f (y) = 21/2 π −1/2 y −1 (sin 2y − sin y). 51. fb(y) =f (y) =∨2−1/2 π 1/2 e−|y| . 52. fb(y) = − f (y) = −i2−1/2 π 1/2 y 3 e−|y| . 65. xH(x).66. (x+1)H(x+1). 67. (2−|x|)H(2−|x|). 68. x3 H(x)/3. 69. (1−cos x)H(x).6370. (x2 −4 sin2 (x/2))H(x). 71. (3x2 +6 cos x−6)H(x). 72. (sh x−sin x)H(x)/2.273. (1 + |x|)e−|x| . 74.
−4−1 a−1/2 xe−ax /2 . 81. πa−1 (ea/2 + e−a/2 R)(ea/2 −te−a/2 )−1 = πa−1 cth a/2. 82. u(t, x) = [f (x−at)+f (x+at)]/2+2−1 0 [g(x−R+∞az) + g(x + az)] dz . 83. f (x, y) = π −1 −∞ y[(x − z)2 + y 2 ]−1 g(z) dz. Óêàçàíèå. Óáåäèòåñü, ÷òî ïðÿìîå ïðåîáðàçîâàíèå Ôóðüå fb(z, y) ôóíêöèè fïî ïåðåìåííîé x èìååò âèä gb(z)e−y|z| .64.