Question

In right ABC, B is a right angle and sin C = x. cos A =

Answer 1

Answer:

cos A = x.

Step-by-step explanation:

Because we have a right-angled triangle,  m < A + m < C = 90 and sin C = Cos A.

So cos A = x.

Answer 2

Answer:

C. $x$.

Step-by-step explanation:

We have been given that in right right ABC, B is a right angle and $\text{sin}(C)=x$. We are asked to find $\text{cos}(A)$.

We will use basic trigonometric identity $\text{sin}(x)=\text{cos}(90-x)$ to solve our given problem.

Since B is the right angle, so by angle sum property $A+90^{\circ}+C=180^{\circ}$

$A+90^{\circ}-90^{\circ}+C=180^{\circ}-90^{\circ}$

$A+C=90^{\circ}$

$A=90^{\circ}-C$

Since $\text{sin}(C)=x$, therefore, by identity $\text{sin}(x)=\text{cos}(90-x)$; $\text{cos}(A)=\text{cos}(90-C)=x$.

Therefore, option C is the correct choice.