Решения к Сборнику заданий по высшей математике Кузнецова Л.А. - 2. Дифференцирование. Зад.15
СОДЕРЖАНИЕ: Задача 15 . Найти производную 15.1. 6t*t y= cos(t /3+t)(t cos(t /3+t)(t +1)t cos(t /3+t) 15.2. (1-t2) 2(1+t)cos (1+t) -(1-tЗадача 15
. Найти производную .
15.1.
x= 6t*t3 -3t2 (3t2 +1) = -t2 -1
3t6 t4
y= cos(t3 /3+t)(t2 +1)
yx = cos(t3 /3+t)(t2 +1)t4 = -t4 cos(t3 /3+t)
-t2 -1
15.2.
x= -t _
(1-t2)
y= 1 _
2(1+t)cos2 (1+t)
yx = -(1-t2 ) = -(1-t2 ) _
2t(1+t)cos2 (1+t) 2tcos2 (1+t)
15.3.
x= 1-t _
(2t-t2 )
y= 2 _
3 3 (1-t)5
yx = 2(2t-t2 ) = 2(2t-t2 ) _
3 3 (1-t)5 (1-t) 3 3 (1-t)2 (1-t)2
15.4.
x= cost = 1
(1-sin2 t)
y= sint = 1
(1-cos2 t)
yx = 1
15.5.
x= 1+t/(t2 +1) = 1 _
t+(t2 +1) (t2 +1)
y= (t2 +1)+ t2 = 2t2 +1_
(t2 +1) (t2 +1)
yx = (2t2 +1)(t2 +1) = 2t2 +1
(t2 +1)
15.6.
x= 1-t _
(2t-t2 )
y= 1 = 1 _
(1-(t-1)2 ) (2t-t2 )
yx = (2t-t2 ) = 1_
(t2-t2 )(1-t) 1-t
15.7.
x= -2et _ = -2et _
sin2 (2et ) 4sin2 et cos2 et
y= et = et _
tget cos2 et sinet coset
yx = 4et sin2 et cos2 et = -2sinet coset
-2et sinet coset
15.8.
x= -1 = -1 _
ctgt sin2 t sint cost
y= 2sint
cos3 t
yx = -cos3 t = -1/2*ctg2 t
2sin2 tcost
15.9.
x= et/2 _
2(1+et )
y= et _
2(1+et )
yx = 2et (1+et ) = (et +e2t )
2et/2 (et +1)
15.10.
x= (1+t) *(1+t) *-1-t-1+t = -1_
(1-t) 2(1-t) (1+t)2 1-t2
y= -t _
(1-t2 )
yx = t(1-t2 ) = t(1-t2 )
(1-t2 )
15.11.
x= 2t3_
1-t4
y= (1+t2 )(-2t(1+t2 )-2t(1-t2 )) = -2
(1+2t2 +t4 -1+2t2 -t4 )(1+t2 )
yx = -2(1-t4 ) = t4 -1
2t3 t3
15.12.
x= -t _
(1-t2 )
y= (1-t2 )+t2 /(1-t2 ) = 1 _
1-t2 (1-t2 )3/2
yx = -(1-t2 )_ = 1_
t(1-t2 )3/2 t3 -t
15.13.
x= -t = -1 _
(1-1+t2 )(1-t2 ) (1-t2 )
y= -2arccost
(1-t2 )
yx = 2arccost(1-t2 ) = 2arccost
(1-t2 )
15.14.
x= (1-t2 )+t2 /(1-t2 ) = 1 _
1-t2 (1-t2 )3/2
y= t *-t2 /(1-t2 )-1-(1-t2 ) = -1
1+(1-t2 ) t2 t
yx = (1-t2 )
t2
15.15.
x= -4(1+cos2 t)costsint
y= -sin3 t-2cos2 tsint = -1-cos2 t
sin4 t sin3 t
yx = 1+cos2 t = 1 _
4sin3 t(1+cos2 t)costsint 4sin4 tcost
15.16.
x= (1+t)(-1-t-1+t) = -2_
(1-t)(1+t)2 1-t2
y= -t _
(1-t2 )
yx = -t (1-t2 )_ = t(1-t2 )
-2(1-t2 ) 2
15.17.
x= 1 = 1 _
t2 (1-1/t2 ) t(t2 -1)
y= t + t = 2t _
(t2 -1) (t2 -1) (t2 -1)
yx = 2t2 (t2 -1) = 2t2
(t2 -1)
15.18.
x= 1_
tln2 t
y= t *-t2 /(1-t2 )-1-(1-t2 ) = -1
1+(1-t2 ) t2 t
yx = -tln2 t = -ln2 t
t
15.19.
x= 1 _
2t(1-t)
y= 1 _
4t(1+t)
yx = 2t(1-t) = (1-t)
4t(1+t) 2
15.20.
x= 2arcsint
(1-t2 )
y= (1-t2 )+t2 /(1-t2 ) = 1 _
1-t2 (1-t2 )3/2
yx = (1-t2 ) = 1 _
2(1-t2 )3/2 arcsint 2(1-t2 )arcsint
15.21.
x= (t2 +1)+t2 /(t2 +1) = 2t2 +1
(t2 +1)
y= t *-t2 /(1-t2 )-1-(1-t2 ) = -1
1+(1-t2 ) t2 t
yx = -(t2 +1) = -1 _
(2t2 +1)(t2 +1) 2t2 +1
15.22.
x= 1/(1+t2 )
y= (t+1)(t(t+1)/(t2 +1)-(1+t2 )) = t-1 _
(1+t2 )(1+t) (t2 +1)(1+t)
yx = (t-1)(1+t2 ) = (t-1)(1+t2 )
(1+t2 )(t+1) 1+t
15.23.
x= -2t/(1-t2 )
y= -t = -1/(1-t2 )
(1-1+t2 )(1-t2 )
yx = 1-t2 = (1-t2 )
2t(1-t2 ) 2t
15.24.
x= (t-1)2 (t-1-t-1) = -1_
((t-1)2 +(t+1)2 )(t-1)2 t2 +1
y= -t = -1/(1-t2 )
(1-1+t2 )(1-t2 )
yx = t2 +1_
(1-t2 )
15.25.
x= (1+sint)(1+sint)(-cost(1+sint)-cost(1-sint)) = -1_
2(1-sint)(1-sint)(1+sint)2 cost
y= tgt/cos2 t-tgt= tg3 t
yx = -tg3 tcost
15.26.
x= 1-2t _ tt(-t-1+t) = (1-t)
2(t-t2 ) 2(t+1-t)(1-t)t2 2t
y= 1 + arcsint _ (1-t) = arcsint
2t 2(1-t) 2t(1-t) 2(1-t)
yx = 2t arcsint = t arcsint
2(1-t) (1-t)
15.27.
x= 1 = 1 _
tgtcos2 t sintcost
y= -2cost
sin3 t
yx = -2cost = -2_
sin4 tcost sin4 t
15.28.
x= (2tlnt+t)(1-t2 )+2t3 lnt – 2t = 2tlnt
(1-t2 )2 2(1-t2 ) (1-t2 )
y= (1-t2 )+t2 /(1-t2 ) arcsint + t/(1-t2 ) – t/(1-t2 ) = arcsint
1-t2 (1-t2 )3/2
yx = arcsint(1-t2 )2 = arcsint(1-t2 )
2tlnt(1-t2 )3/2 2tlnt
15.29.
x= 2esec^2t sec2 t tgt= 2esec^2t sint
cos3 t
y= lncost _ sint + 1/cos2 t-1= lncost-sintcost+sin2 t
cos2 t cost cos2 t
yx = 1/2*e-sec^2t ctgt(lncost-sintcost+sin2 t)
15.30.
x= (1-t2 )+t2 /(1-t2 ) arcsint + t/(1-t2 ) – t/(1-t2 ) = arcsint
1-t2 (1-t2 )3/2
y= (1-t2 )+t2 /(1-t2 ) = 1 _
1-t2 (1-t2 )3/2
yx = (1-t2 )3/2 = 1 _
(1-t2 )3/2 arcsint arcsint
15.31.
x= 1+t/(t2 +1) = 1 _
t+(t2 +1) (t2 +1)
y= t _ t *-t2 /(1-t2 )-1-(1-t2 ) = t + 1 = t2 +2(1-t2 )
2(1+t2 ) 1+(1-t2 ) t2 2(1+t2 ) t 2t(1-t2 )
yx = (t2 +2(1-t2 ))(1+t2 )
2t(1-t2 )