Posted by andi telaumbanua on Feb 13, 2018 in
Matematika
Tentukan turunan pertama dari y = sin x tan (x^2+1) !
Jawab:
Gunakan aturan rantai
Pertama kita menurunkan tan (x^2+1)
Misalkan : u = x^2+1
maka: du/dx=2x
Sehingga : y = tan u
maka : dy/du= sec^2 u= sec^2 (x^2+1)
Maka:
dy/dx= ( dy/du ) (du/dx)=(sec^2 (x^2+1) )(2x)=2xsec^2 (x^2+1)
Kemudian:
y = ab
maka: y^’=a^’ b+ab^’
Maka:
y^’=(cosx) (tan (x^2+1)) + (sinx)(2xsec^2 (x^2+1))
y^’=cosx tan (x^2+1) + 2x sinx sec^2 (x^2+1)
for more clear writing please click the link below
Posted by andi telaumbanua on Feb 13, 2018 in
Matematika
Tentukan turunan pertama dari y = cos^4 (4x^2- x) !
Jawab:
Gunakan aturan rantai
Misalkan: a = (4x^2- x)
maka: da/dx=8x-1
Misalkan: b = cos a
maka: db/da=-sina = -sin(4x^2- x)
Sehingga: y = b^4
maka: dy/db=4b^3 = 4(cos a)^3 = 4[cos(4x^2- x)]^3
Maka: dy/db=4 cos^3 (4x^2- x)
Sehingga:
dy/dx = (dy/db)(db/da)(da/dx)
dy/dx = (4 cos^3 (4x^2- x) )(-sin(4x^2- x) )(8x-1)
dy/dx = [8x-1] [-4cos^3 (4x^2- x) sin(4x^2- x)]
dy/dx = [-32x cos^3 (4x^2- x) sin(4x^2- x)] – [-4〖cos〗^3 (4x^2- x) sin(4x^2- x)]
dy/dx = 4cos^3 (4x^2- x) sin(4x^2- x) – 32x cos^3 (4x^2- x) sin(4x^2- x)
Posted by andi telaumbanua on Feb 13, 2018 in
Matematika
Tentukan turunan pertama dari y = sin^3 x !
Jawab:
Gunakan aturan rantai
Misalkan : u = sin x
maka: du/dx=cosx
Sehingga : y = u^3
maka : dy/du=3u^2=3(sinx)^2 = 3sin^2 x
Maka:
dy/dx= ( dy/du ) (du/dx)=(3sin^2 x )(cosx )= 3sin^2 x cosx
for more clear writing please click the link below
Posted by andi telaumbanua on Feb 13, 2018 in
Matematika
Tentukan turunan pertama dari y = [(x+1)/(x-1)]^2 !
Jawab:
Gunakan aturan rantai
Misalkan :
u = (x+1)/(x-1)
maka:
du/dx = [ 1(x-1) – (x+1)1 ] / (x-1)^2
du/dx = -2 /(x-1)^2
Sehingga : y = u^2
maka :
dy/du = 2u
dy/du = 2[(x+1) / (x-1)]
dy/du = (2x+2) / (x-1)
Maka:
dy/dx = ( dy/du ) (du/dx)
dy/dx = [(2x+2)/(x-1)] [-2 / (x-1)^2]
dy/dx = (-4x – 4) / (x-1)^3
for more clear writing please click the link below
Posted by andi telaumbanua on Feb 13, 2018 in
Matematika
Tentukan turunan pertama dari bentuk implisit x^2 sin(xy)+y = x !
Jawab : Turunan bentuk implisit
Pertama kita turunkan dulu sin (xy)
Misalkan : u = xy maka: du/dx=(1)(y)+ (x)(dy/dx)=y+x dy/dx
Maka: y = sin u maka: dy/du=cosu=cos(xy)
Sehingga :
dy/dx = (dy/du)(du/dx)
dy/dx = (cos(xy) )(y+x dy/dx)
dy/dx = y cos(xy) + x cos(xy) dy/dx
Kedua kita turunkan x^2 sin(xy)
d[x^2 sin(xy)]/dx = 2xsin(xy) + x^2 [y cos(xy) + x cos(xy) dy/dx]
d[x^2 sin(xy)]/dx = 2xsin(xy) + x^2 y cos(xy) + x^3cos(xy) dy/dx
Maka:
maka turunan x^2 sin(xy)+ y = x adalah
d[x^2 sin(xy)] /dx + dy/dx = dx/dx
2xsin(xy) + x^2 y cos(xy) + x^3cos(xy) dy/dx + dy/dx = 1
dy/dx [x^3cos(xy) + 1] = 1-2x sin(xy) – x^2 y cos(xy)
dy/dx = [1- 2x sin(xy) – x^2 y cos(xy)] / [x^3cos(xy) + 1]