1. Turunan dari y = cos2 ((x^(2 )+2)/(x^2-2)) adalah.... a. -2 cos((x^(2 )+2)/(x^2-2)) sin ((x^(2 )+2)/(x^2-2)) b. 2((x^(2 )+2)/(x^2-2)) cos((x^(2 )+2)/(x^2-2)) sin ((x^(2 )+2)/(x^2-2)) c. 16x/((x^2 〖-2)〗^2 ) cos((x^(2 )+2)/(x^2-2)) sin ((x^(2 )+2)/(x^2-2)) d. 2((x^(2 )+2)/(x^2-2)) 16x/((x^2 〖-2)〗^2 ) cos((x^(2 )+2)/(x^2-2)) sin ((x^(2 )+2)/(x^2-2)) 2. Volume benda yang terbentuk dengan memutar mengelilingi sumbu –x daerah yang dibatasi oleh garis x-2y = 0 dan parabola y^2 = 4x adalah.... satuan volume a. 512/3 π b. 6561/4 π c. 704/5 π d. 1024/35 π
y = cos^2 ((x^2 + 2)/(x^2 - 2) = cos^2 f y' = 2 cos f . - sin f . f' = -2 f' cos f sin f = -2 (-8x)/(x^2 - 2)^2 . cos ((x^2 + 2)/(x^2 - 2)) sin ((x^2 + 2)/(x^2 - 2)) = (16x)/(x^2 - 2)^2 . cos ((x^2 + 2)/(x^2 - 2)) sin ((x^2 + 2)/(x^2 - 2))
2) y^2 = 4x => x = 1/4 y^2 x - 2y = 0 => x = 2y
Titik potong : x = x 1/4 y^2 = 2y y^2 = 8y y^2 - 8y = 0 y (y - 8) = 0 y = 0 atau y = 8 ====> sebagai batas integral
V = π int ((2y)^2 - (1/4 y^2)^2 dy = π int (4y^2 - 1/16 y^4) dy = π (4/3 y^3 - 1/80 y^5) | batas 0 sampai 8 = π [4/3 (8)^3 - 1/80 (8)^5 - 0] = π [2048/3 - 2048/5] = [10240 - 6144]/15 π = 4096/15 π
Verified answer
Luas bayangan ABC dengan A(2,0) , B(6,0) , C(4,2) oleh transformasi matriks ( 1 dibawahnya 0 dan 1 dibawahnya 3) adalah...Please jawab dengan dengan langkah nya
u = x^2 + 2 => u' = 2x
v = x^2 - 2 => v' = 2x
f' = (u' v - v' u)/v^2
= (2x (x^2 - 2) - 2x(x^2 + 2)) / (x^2 - 2)^2
= (2x^3 - 4x - 2x^3 - 4x) / (x^2 - 2)^2
= (-8x) / (x^2 - 2)^2
y = cos^2 ((x^2 + 2)/(x^2 - 2) = cos^2 f
y' = 2 cos f . - sin f . f'
= -2 f' cos f sin f
= -2 (-8x)/(x^2 - 2)^2 . cos ((x^2 + 2)/(x^2 - 2)) sin ((x^2 + 2)/(x^2 - 2))
= (16x)/(x^2 - 2)^2 . cos ((x^2 + 2)/(x^2 - 2)) sin ((x^2 + 2)/(x^2 - 2))
2) y^2 = 4x => x = 1/4 y^2
x - 2y = 0 => x = 2y
Titik potong : x = x
1/4 y^2 = 2y
y^2 = 8y
y^2 - 8y = 0
y (y - 8) = 0
y = 0 atau y = 8 ====> sebagai batas integral
V = π int ((2y)^2 - (1/4 y^2)^2 dy
= π int (4y^2 - 1/16 y^4) dy
= π (4/3 y^3 - 1/80 y^5) | batas 0 sampai 8
= π [4/3 (8)^3 - 1/80 (8)^5 - 0]
= π [2048/3 - 2048/5]
= [10240 - 6144]/15 π
= 4096/15 π