Answer :
Step by step explanation :
We know,
sin θ = [tex]\:\mathsf{\frac{opposite}{hypotenuse}}[/tex]
here,
sin 0 = [tex]\:\mathsf{\frac{2}{5}}[/tex]
So,
opposite must be 2
and hypotenuse will be 5
Now,
By Pythagoras theorem
Adjacent = [tex]\:\mathsf{\sqrt(hypotenuse²)-(opposite²)}[/tex]
=> Adjacent = [tex]\:\mathsf{\sqrt(5²)-(2²)}[/tex]
=> Adjacent = [tex]\:\mathsf{\sqrt(25)-(4)}[/tex]
=> Adjacent = [tex]\:\mathsf{\sqrt(21)}[/tex]
Now as adjacent = [tex]\:\mathsf{\sqrt(21)}[/tex]
We know,
cos θ = [tex]\:\mathsf{\frac{Adjacent}{hypotenuse}}[/tex]
=> cos θ = [tex]\:\bf\boxed{\frac{√21}{5}}[/tex]
Hope this helps you!
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The calculation is lengthy but if you know the concept then it's very easy
I would suggest you to learn all the trigonometric ratios and these trigonometric functions.
Thank you!
