Tolong dibantu, jawabanya apa sekalian sama caranya. no 10

Tolong dibantu, jawabanya apa sekalian sama caranya. no 10

Jawaban Terkonfirmasi

$intlimits^1_a 12x(x^{2} + 1)^{2} dx = 14 \\ misal : \\ u = x^{2} + 1 \ frac{du}{dx} = 2x \\ dx = frac{du}{2x} \\ ========== \\ intlimits^1_a 12x(x^{2} + 1)^{2} = intlimits^1_a frac{12x(u)^{2}}{2x} du \\ = intlimits^1_a 6u^{2} du \\ = [2u^{3}]^1_a$

$= [2(x^{2} + 1)^{3}]^1_a \\ (2((1)^{2} + 1)^{3}) - (2((a)^{2} + 1)^{3}) = 14 \\ 2(2)^{3} - 2(a^{2} + 1)^{3} = 14 \\ 16 - 2(a^{2} + 1)^{3} = 14 \\ -2(a^{2} + 1)^{3} = -2 \\ 2(a^{2} + 1)^{3} = 2 \\ (a^{2} + 1)^{3} = 1 \\ a^{2} + 1 = sqrt[3]{1} \\ a^{2} + 1 = 1 \\ a^{2} = 0 \\ boxed{boxed{bold{ a = 0}}}$

$rightarrow C.$