Question

1/1+tg^2a + 1/ cos^2a +1​

Answer 1

Ответ:  Объяснение:  1+tg^2a=1/cos^2;  (cos^2a/cos^2a) +    +sin^2a/cos^2a=1/cos^2;  (cos^2+sin^2)/cos^2a=1/cos^2a;  1/cos^2a=1/cos^2a.  Тождество доказано.

Answer 2

To simplify the expression, let's use some trigonometric identities:

1. Recall that the tangent squared identity is: tan^2(a) + 1 = sec^2(a)

2. Also, the secant squared identity is: sec^2(a) = 1/cos^2(a)

Now, we can rewrite the expression using these identities:

1 + tan^2(a) + 1/cos^2(a) + 1

Replace tan^2(a) with sec^2(a) - 1:

1 + sec^2(a) - 1 + 1/cos^2(a) + 1

Now, replace sec^2(a) with 1/cos^2(a):

1 + 1/cos^2(a) + 1/cos^2(a) + 1

Now, combine like terms:

1 + 2/cos^2(a) + 1

Now, simplify further:

2/cos^2(a) + 2

Finally, we can rewrite this in a more standard form:

2(1/cos^2(a) + 1)

The simplified expression is 2(1/cos^2(a) + 1).