<span>b^4 − b^3 + b − 1
=(</span><span>b^4 − b^3) + (b − 1)
= b^3(b - 1) + (b - 1)
=(b - 1)(b^3 + 1)</span>
We know that
sin²x+cos²x=1
so
clear cos x
cos x=(+/-)√[1-sin²x]
in this problem
<span>Angle 0 is in quadrant 1 -----> cos o and sin o are positive
</span>sin o=2/5
cos x=√[1-(2/5)²]----> cos o=√[1-4/25]----> cos o=√[21/25]---> cos o=√21/5
the answer is
cos o=√21/5
I also need this answer so when you find out let me know
Answer:
x = 
Step-by-step explanation:
Given
A = 
xy
Multiply both sides by 2 to clear the fraction
2A = xy ( divide both sides by y )
= x
Answer:
Step-by-step explanation:
<u>Use trigonometry to help</u>
- cos = adjacent side/hypotenuse
- hypotenuse = adjacent side / cos
<u>Substitute values:</u>
- Distance between the Sun and the Moon = y / cos x
