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
Answer:

Step-by-step explanation:
a reciprocal is a number that when multiplied by a given number gives 1 as product.
16 * x = 1
x = 1/16
9/10 * x = 1
x = 10/9
Answer:
The vertex of the function is at (2,3).
Step-by-step explanation:
I graphed the equation on the graph below.
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Answer:
4.2
Step-by-step explanation:
You just have to subtract the two fractions and put it in decimal form.
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Step-by-step explanation:
Multiply the first equation by 7 and the second by 2