Answer:
Step-by-step explanation:
Your answer is 6
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
Start by decomposing the number inside the root into primes
Then group the terms into cubes if possible
![\begin{gathered} 80=2\cdot2\cdot2\cdot2\cdot5 \\ 80=2^3\cdot2\cdot5 \\ 80=10\cdot2^3 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%2080%3D2%5Ccdot2%5Ccdot2%5Ccdot2%5Ccdot5%20%5C%5C%2080%3D2%5E3%5Ccdot2%5Ccdot5%20%5C%5C%2080%3D10%5Ccdot2%5E3%20%5Cend%7Bgathered%7D)
rewrite the root
![\sqrt[3]{80}=\sqrt[3]{10\cdot2^3}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B80%7D%3D%5Csqrt%5B3%5D%7B10%5Ccdot2%5E3%7D)
then cancel the terms that are cubes and bring them out of the root
The answer would be: <span>√x+3=13
</span>A radical equation is an equation with at least one variable put on a radical form. In this question, there is only one kind of variable which is x. Then, you need to find the equation where x is in the radical form. The radical form can be expressed with square root symbol.
The option with √x would be only <span>√x+3=13
</span>
I think the answer is 5x−68