Mohon bantuannya Sertakan langkahnya

<p>&nbsp;</p><p>Jawaban &nbsp;&nbsp;<strong>C. &nbsp;-1</strong></p><p>&nbsp;</p><p><strong>Pembahasan&nbsp;</strong></p><p>f(x) = sin x(1 + cos x)&nbsp;</p><p>&nbsp; &nbsp; &nbsp; &nbsp;= sin x + sin x. cos x</p><p>f'(x) = cos x + (cos x. cos x + sin x. -sin x)&nbsp;</p><p>&nbsp; &nbsp; &nbsp; &nbsp;= cos x + cos²x - sin²x&nbsp;</p><p>f"(x) = -sin x + (2 cos x. -sin x) - (2 sin x. cos x)&nbsp;</p><p>&nbsp; &nbsp; &nbsp; &nbsp; = -sin x - 4 sin x. cos x</p><p>&nbsp; &nbsp; &nbsp; &nbsp;</p><p>f"(π/2) = -sin π/2 - 4 sin π/2. cos π/2</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= -1 - 4.1.0</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= &nbsp;-1</p>