Answer :

Let's solve the expression step by step to find the value of [tex]\(\frac{4}{3} \tan^2 30^{\circ} + \sin^2 60^{\circ} + \frac{3}{4} \tan^2 60^{\circ} - 2 \tan^2 45^{\circ}\)[/tex].

1. Calculate [tex]\(\tan^2 30^{\circ}\)[/tex]:

First, remember that [tex]\(\tan 30^{\circ} = \frac{1}{\sqrt{3}}\)[/tex].

[tex]\[ \tan^2 30^{\circ} = \left( \frac{1}{\sqrt{3}} \right)^2 = \frac{1}{3} \][/tex]

Now calculate [tex]\(\frac{4}{3} \tan^2 30^{\circ}\)[/tex]:

[tex]\[ \frac{4}{3} \tan^2 30^{\circ} = \frac{4}{3} \cdot \frac{1}{3} = \frac{4}{9} \approx 0.444444 \][/tex]

2. Calculate [tex]\(\sin^2 60^{\circ}\)[/tex]:

Recall that [tex]\(\sin 60^{\circ} = \frac{\sqrt{3}}{2}\)[/tex].

[tex]\[ \sin^2 60^{\circ} = \left( \frac{\sqrt{3}}{2} \right)^2 = \frac{3}{4} = 0.75 \][/tex]

3. Calculate [tex]\(\tan^2 60^{\circ}\)[/tex]:

We know [tex]\(\tan 60^{\circ} = \sqrt{3}\)[/tex].

[tex]\[ \tan^2 60^{\circ} = (\sqrt{3})^2 = 3 \][/tex]

Now calculate [tex]\(\frac{3}{4} \tan^2 60^{\circ}\)[/tex]:

[tex]\[ \frac{3}{4} \tan^2 60^{\circ} = \frac{3}{4} \cdot 3 = \frac{9}{4} = 2.25 \][/tex]

4. Calculate [tex]\(\tan^2 45^{\circ}\)[/tex]:

Remember that [tex]\(\tan 45^{\circ} = 1\)[/tex].

[tex]\[ \tan^2 45^{\circ} = 1^2 = 1 \][/tex]

Now calculate [tex]\(2 \tan^2 45^{\circ}\)[/tex]:

[tex]\[ 2 \tan^2 45^{\circ} = 2 \cdot 1 = 2 \][/tex]

5. Combine all terms:

Now, add the terms together and subtract the last term:

[tex]\[ \frac{4}{3} \tan^2 30^{\circ} + \sin^2 60^{\circ} + \frac{3}{4} \tan^2 60^{\circ} - 2 \tan^2 45^{\circ} \][/tex]

Substituting the calculated values:

[tex]\[ 0.444444 + 0.75 + 2.25 - 2 \][/tex]

Simplify this expression:

[tex]\[ 0.444444 + 0.75 + 2.25 - 2 = 1.444444 \][/tex]

So, the value of the given expression is [tex]\(1.444444\)[/tex].