Answer:
D. Pythagorean
Step-by-step explanation:
Given the identity
cos²x - sin²x = 2 cos²x - 1.
To show that the identity is true, we need to show that the left hand side is equal to right hand side or vice versa.
Starting from the left hand side
cos²x - sin²x ... 1
According to Pythagoras theorem, we know that x²+y² = r² in a right angled triangle. Coverting this to polar form, we have:
x = rcostheta
y = rsintheta
Substituting into the Pythagoras firnuka we have
(rcostheta)²+(rsintheta)² = r²
r²cos²theta+r²sin²theta = r²
r²(cos²theta+sin²theta) = r²
(cos²theta+sin²theta) = 1
sin²theta = 1 - cos²theta
sin²x = 1-cos²x ... 2
Substituting equation 2 into 1 we have;
= cos²x-(1-cos²x)
= cos²x-1+cos²x
= 2cos²x-1 (RHS)
This shows that cos²x -sin²x = 2cos²x-1 with the aid of PYTHAGORAS THEOREM
Answer:
n=log(9 1/5)
Step-by-step explanation:
Answer:
4x-4/x^2
Step-by-step explanation:
So we can first write out the equation.
It would be:
8/2x-4/x^2
First we can get a common denominator:
8/2x*x^2/x^2=8x^2/2x^3
and
4/x^2*2x/2x=8x/2x^3
Now we have
8x^2/2x^3-8x/2x^3
or
8x^2-8x/2x^3
We can divide everything by x
8x-8/2x^2
divide everything by 2
4x-4/x^2
It’s probably A. (1,2) hope this helps..
Answer:
<T
Step-by-step explanation:
You can tell that the angles and length of the triangles are equal from the marks. For example, angle J has 2 lines on its angle so i looked for the other angle with 2 lines on it which happens to be angle S.
Comment if u dont understand
