7.
Diketahui f(x) =
ƒ'(x) =
=
A. -7
B. -2
C. 0
COS X
sin x - 7°
a sin x + b
(sin x-7)²²
Jika
nilai a ⋅ b = ...
·
D. 1
E.
14
Diketahui f(x) =
ƒ'(x) =
=
A. -7
B. -2
C. 0
COS X
sin x - 7°
a sin x + b
(sin x-7)²²
Jika
nilai a ⋅ b = ...
·
D. 1
E.
14
Penjelasan dengan langkah-langkah:
no. 7
gunakan rumus
f(x) = u/v
f'(x) = (u'.v - u.v')/v²
f(x) = cosx/(sinx - 7)
f'(x) = [-sinx(sinx -7) - (cosx,cosx)]/(sinx - 7)²
f'(x) = [-sin²x + 7sinx - cos²x ] / (sin - 7)²
f'(x) = [-sin²x + 7sinx - (1 - sin²x)] / (sinx - 7)²
f'(x) = [-sin²x + 7sinx - 1 + sin²x] / (sinx - 7)²
f'(x) = (7sinx - 1) / (sinx - 7)²
a = 7
b = -1
nilai dari :
a x b
= 7 x (-1)
= -7
jawabannya : A