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
Area of parallelogram = width x height
Area of parallelogram = 3.1 x 3.5
Area of parallelogram = 10.85 unit²
Answer:
22.5 miles per hour
Step-by-step explanation:
<u>Given system of equations</u>
5(s-w)=900
4(s+w)=900
<u />
<u>Set equations equal to each other</u>
5(s-w)=4(s+w)
5s-5w=4s+4w
s-5w=4w
s=9w
<u>Solve for w using the substitution s=9w</u>
4(s+w)=900
4(9w+w)=900
4(10w)=900
40w=900
w=22.5
Therefore, the speed of the wind is 22.5 miles per hour
Answer:
Part 1: The option (A) is correct. The prediction of the event is 32 spins.
Part 2: Option (B) is correct. The probability of the event is 139 passwords.
Part 3: The P(yellow or blue) is 2/6.
Part 4: Option (B) is correct.
Part 5: Both options (A) and (C) are correct.
Step-by-step explanation:
please brainless
<span>[ (3x6) ] + (5x2) ] ÷ 7
= (18 + 10)/7
= 28/7
= 4</span>
