Ok.. So I see a recurring theme that we do not cover in any of my lecture notes. This is a trig function. COS²θ - SIN²θ = 1 I have to demonstrate why COS²θ MINUS SIN²θ = 1... But every transformation I make leads me to believe that this can never be true. Help?

Because the actual identity says  

Step-by-step explanation:

The trigonometric ratios and have a maximum value of 1. And hence and will have values between 0 and 1 as they are squares and will be always positive.

But if we look at the equation shows that will be more than 1. Hence it is an incorrect equation.

The correct relation between and is .

in simplified version   it would be x ≤-4

step-by-step explanation:

multiply each term in x ≤-4 by -1

their is no graph showing

step-by-step explanation: