Question

The slope of the tangent to the curve $y=sinx$ where it crosses the $x-axis$ is

• A. $1$
• B. $-1$
• C. $\pm 1$
• D. $\pm 2$

Answer 1

Answer: (A)

$1$

Consider the given equation of the curve.

$y=\sin x$ ……(1)

On differentiating equation (1) with respect to $x$, we get

$\frac{dy}{dx}=\cos x$

When given curve crosses the x-axis then.

$y=0$

$\sin x=0$

$x=0$

Therefore,

${\left(\frac{dy}{dx}\right)}_{y=0}=\cos 0$

${\left(\frac{dy}{dx}\right)}_{y=0}=1$

Hence, this is the answer.