Question

evslute 2 tan 45+cos2 30-sin2 60°

Answer 1

2tan 45 + cos^2 30 - sin^2 60

=> 2tan45 + cos^2 30 - sin^2 ( 90 - 30 )

=> 2tan45 + cos^2 30 - cos^2 30

=> 2tan45

=> 2 ( 1 ) [ we know, tan45 = 1 ]

=> 2

Method 2 :

2tan 45 + cos^2 30 - sin^2 60

$\rightarrow 2 ( 1 ) + ( \frac{\sqrt{3}}{2} )^2 - ( \frac{\sqrt{3}}{2} )^2\\ \\ \rightarrow 2 + \frac{3}{4} - \frac{3}{4} \\ \\ \rightarrow 2$

Answer 2

2tan 45 + cos^2 30 - sin^2 60

=> 2tan45 + cos^2 30 - sin^2 ( 90 - 30 )

=> 2tan45 + cos^2 30 - cos^2 30

=> 2tan45

=> 2 ( 1 ) [ we know, tan45 = 1 ]

=> 2

Method 2 :

2tan 45 + cos^2 30 - sin^2 60

$\rightarrow 2 ( 1 ) + ( \frac{\sqrt{3}}{2} )^2 - ( \frac{\sqrt{3}}{2} )^2\\ \\ \rightarrow 2 + \frac{3}{4} - \frac{3}{4} \\ \\ \rightarrow 2$