using the formula, sin A=whole root 1-cos A/2, find the value of sin30,it being given that cos60=1-2

Open in App

Solution

we have to find the value of sin30
put 30 instead of A in ouestion then it become
Sin30=root(1-cos2{30})/2
=) Sin30=root(1-cos60)/2
=)Sin30=root(1-1/2)/2 given that cos60=1/2
=)Sin30=root(1/2)/2
=)Sin30=root(1/4)
=) Sin30=1/2

Suggest Corrections

Similar questions

\sin A = \sqrt{\frac{1 - \cos 2 A}{2}}

\frac{1}{2}

cos A = \sqrt{\frac{1 + cos 2 A}{2}},

cos 30^{\circ}

cos 60^{\circ} = \frac{1}{2}

c o s A = \sqrt{\frac{1 + c o s 2 A}{2}},

c o s 30^{0}

c o s 60^{0} = \frac{1}{2} .

\cos A = \sqrt{\frac{1 + \cos 2 A}{2}}

\frac{1}{2}

If sinA - cos A = 1/2, then find the value of 1/(sinA+cosA)

Join BYJU'S Learning Program