jika 0 ≤ θ ≤ π/2 dan tan θ = X, nilai tan θ + sin θ cos θ = ....

(t) = teta
Tan t = x
Tan² t = x²
Tan²t - 1 = x²-1
1/cos²t = x²-1
cos²t= 1 / x²-1
Cost= √(1 / x²-1)
cost=

Cos²t= 1 / x²-1
sint= √ 1- (1 / x²-1)
sint = √(x²-1-1 / x²-1
sint = √(x²-2 / x²-1)

sintcost= √(1 / (x²-1) x √(x²-2 / x²-1)
=√1 / √(x²-1) x (√x²-2) / √x²-1
=√(x²-2) / x²-1


maka
Tan t + sintcost =
= x + √(x²-2) / x²-1
=x(x²-1) + √(x²-2) / x²-1
= x³-x+√x²-2 / x²-1