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
Those are positive numbers.
Those that are less than zero are called negative numbers.
Zero itself can be considered both, or neither.
Answer:
A
Step-by-step explanation:
We can substract the wavength of the violet light to the wavelength of the red light:
(6.5 x 10^-7 m) - (4.0 x 10^-7 m) = 2.5 x 10^-7 m
<span>g(x)= 3x − 3
</span><span>g(−6)
g(-6) = 3(-6) - 3
g(-6) = -18 - 3
g(-6) = -21
The answer is -21.</span>
Answer:
<u>the amount saved in buying a pair of $32.95 blue jeans on sale for $26.50</u>
Step-by-step explanation:
all are pretty good answers but that one is most reasonable
have a nice day :)