4.92.
4 is a whole number, so it goes in the ones place
The ths means it is going to be a decimal, so 92 goes two right of the decimal point. Hope this helped
I think the answer is 716.7 not 100% positive
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
You can do it this think and if you can't I will help you
