Question

Prove that:random answer will be reported.​

Answer 1

i think the best answer is b.cos60 + sin60+1/8(5 +3cos40) the answer is -0.88232537463→

a

3

+

b

3

=

(

a

+

b

)

(

a

2

−

a

b

+

b

2

)

→

a

2

+

b

2

=

(

a

−

b

)

2

+

2

a

b

→

sin

2

x

+

cos

2

x

=

1

→

2

cos

2

x

=

1

+

cos

2

x

and

→

2

sin

2

x

=

1

−

cos

2

x

L

H

S

=

cos

6

(

x

)

+

sin

6

(

x

)

=

(

cos

2

x

)

3

+

(

sin

2

x

)

3

=

[

cos

2

x

+

sin

2

x

]

[

(

cos

2

x

)

2

−

cos

2

x

⋅

sin

2

x

+

sin

2

x

)

2

]

=

1

⋅

[

(

cos

2

x

−

sin

2

x

)

2

+

2

cos

2

x

⋅

sin

2

x

−

cos

2

x

⋅

sin

2

x

]

=

[

cos

2

(

2

x

)

+

cos

2

x

⋅

sin

2

x

]

=

1

4

[

4

cos

2

(

2

x

)

+

4

cos

2

x

⋅

sin

2

x

]

=

1

4

[

2

(

1

+

cos

4

x

)

+

sin

2

(

2

x

)

]

=

2

4

⋅

2

[

2

+

2

cos

4

x

+

sin

2

(

2

x

)

]

=

1

8

[

4

+

4

cos

4

x

+

2

sin

2

(

2

x

)

]

=

1

8

[

4

+

4

cos

4

x

+

1

−

cos

4

x

]

=

1

8

[

5

+

3

cos

4

x

]

=

R

H

S