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: C) as x → -∞, y → 3
as x→ ∞ , y → ∞
<u>Step-by-step explanation:</u>
see graph
Notice that as x approaches negative infinity (goes to the left), the y value approaches the asymptote of y = 3.
And as x approaches positive infinity (goes to the right), the y-value increases without bound so goes to infinity.
Answer:
6 more students
Step-by-step explanation:
hope this helps
Answer:
11/2
Step-by-step explanation:
6x−7=26
Step 1: Add 7 to both sides.
6x−7+7=26+7
6x=33
Step 2: Divide both sides by 6.
x= 11/2