Tolong bagi siapa saja smart people yg bisa,bantu saya ​

Penjelasan dengan langkah-langkah:

no. 1

f(x – 1) = 2x + 3

misal

a = x – 1

x = a – 1

f(a) = 2(a + 1) + 3

f(a) = 2a + 2 + 3

f(a) = 2a + 5

f(x) = 2x + 5

(fog)(x) = 20x + 15

f(g(x) = 20x + 15

2g(x) + 5 = 20x + 15

2g(x) = 20x + 10

g(x) = 10x + 5

.

no.2

f(x) = (2x – 1)/(2x + 7)

g(x) = 3x + 4

(fog)(x) = [2(3x + 4) – 1]/[2(3x + 4) + 7]

(fog)(x) = (6x + 5) /(6x + 15)

y = (6x + 5)/(6x + 15)

y(6x + 15) = (6x + 5)

6yx + 15y = 6x + 5

6yx – 6x = -15y + 5

x(6y – 6) = -15y + 5

x = (-15y + 5)/(6y – 6)

(fog)⁻¹(x) = (-15x + 5)/(6x – 6)

.

no.3

tanθ – cotθ = (1 – 2cos²θ)/(sinθ cosθ)

tanθ – cotθ

= sinθ/cosθ – cosθ/sinθ

= sin²θ/sinθcosθ – cos²θ/sinθcosθ

= (sin²θ – cos²θ)/sinθcosθ

= (1 – cos² – cos²θ)/sinθcosθ

= (1 – 2cos²θ)/sinθcosθ