Question

True or false (Picture provided)

Answer 1

Hello!

The answer is: True.

Why?

A counterexample is a way that we can prove that something is not true about a mathematical expression or equation, it could be considered as an exception to a rule, so to check if the answer is true or false, we must prove that a counterexample of the given expression is 0°, so:

The given expression is:

$sinytany=cosy$

Then,

$sin(0)*\frac{sin(0)}{cos(0)}=cos(0)\\\\0*\frac{0}{1}=1\\\\0*0=1\\0=1$

We can see that the equation is not fulfilled, so 0° is a counterexample of $sinytany=cosy$ and the answer is true.

Have a nice day!