To find: tan2x
From part (i) and (ii), we have
sin2x = \(\frac{4\sqrt{5}}{9}\)
And 2x = -\(\frac{1}{9}\)
We know that,
tanx = \(\frac{sinx}{cosx}\)
Replacing x by 2x, we get
tan2x = \(\frac{sin2x}{cos2x}\)
Putting the values of sin 2x and cos 2x, we get
∴ tan2x = -4√5