Jawaban:

c.120 cm²

Penjelasan dengan langkah-langkah:

\begin{gathered} \frac{ \cos^{4} \alpha - \sin^{4}\alpha }{1 - tan^{4} \alpha } \\ \frac{( \cos^{4} \alpha - \sin^{4} \alpha)}{1 - \frac{ \sin^{4} \alpha}{ \cos^{4} \alpha} } \\ \frac{( \cos^{4} \alpha - \sin^{4} \alpha) }{ \frac{ \cos^{4} \alpha}{ \cos^{4} \alpha} - \frac{ \sin^{4} \alpha}{ \cos^{4} \alpha} } \\ \frac{( \cos^{4} \alpha - \sin^{4} \alpha) }{ \frac{( \cos^{4}\alpha - \sin^{4} \alpha) }{ \cos^{4} \alpha} } \\ \frac{( \cos^{4} \alpha - \sin^{4} \alpha)(\cos^{4} \alpha)}{(\cos^{4} \alpha - \sin^{4} \alpha) } \\ coret \: yg \: sama \\ cos^{4} \alpha \end{gathered}

1−tan

4

α

cos

4

α−sin

4

α

1−

cos

4

α

sin

4

α

(cos

4

α−sin

4

α)

cos

4

α

cos

4

α

−

cos

4

α

sin

4

α

(cos

4

α−sin

4

α)

cos

4

α

(cos

4

α−sin

4

α)

(cos

4

α−sin

4

α)

(cos

4

α−sin

4

α)

(cos

4

α−sin

4

α)(cos

4

α)

coretygsama

cos

4

α

semoga membantu