secx+tanx/secx- tanx = 1+2sinx+sin^2x/ cos^2x

I will assume you want to prove the identity to be true.

The way you typed , the statement is NOT an identity
You must have meant:
(secx+tanx)/(secx- tanx) = (1+2sinx+sin^2x)/ cos^2x

LS = (1/cosx + sinx/cosx) / (1/cosx - sinx/cosx)
= ( (1+sinx)/cosx)/( (1-sinx)/cosx)
= (1+sinx) / (1 - sinx)

RS = (1+sinx)^2 / (1 - sin^2 x)
= (1+sinx)(1+sinx)/( (1-sinx)(1+sinx))
= (1+sinx)/(1-sinx)
= LS

To simplify the expression secx+tanx/secx-tanx, we can start by rationalizing the denominator.

We're given the expression: secx+tanx/secx-tanx

To rationalize the denominator, we multiply both the numerator and denominator by the conjugate of the denominator, which is secx + tanx:

(secx+tanx/secx-tanx) * (secx+tanx/secx+tanx)

When we multiply the numerator and denominator, we get:

(sec^2x + secx*tanx + secx*tanx + tan^2x) / (sec^2x - tan^2x)

This simplifies to:

(sec^2x + 2secx*tanx + tan^2x) / (sec^2x - tan^2x)

Now, we can apply the trigonometric identity:

sec^2x - tan^2x = 1

Substituting this identity in, we have:

(sec^2x + 2secx*tanx + tan^2x) / 1

Simplifying further, we get:

sec^2x + 2secx*tanx + tan^2x

Next, let's simplify the numerator of the expression 1 + 2sinx + sin^2x:

Using the identity cos^2x + sin^2x = 1, we can rewrite sin^2x as 1 - cos^2x:

1 + 2sinx + sin^2x = 1 + 2sinx + (1 - cos^2x)

Combining like terms, we have:

2 + 2sinx - cos^2x

Now, let's simplify cos^2x. Using the identity sin^2x + cos^2x = 1, we can rewrite cos^2x as 1 - sin^2x:

2 + 2sinx - cos^2x = 2 + 2sinx - (1 - sin^2x)

Distributing the negative sign, we get:

2 + 2sinx - 1 + sin^2x

Combining like terms, we have:

1 + 2sinx + sin^2x

Comparing this to the numerator of our rationalized expression, we can see that they are equal.

Therefore, we can conclude that:

(secx+tanx/secx-tanx) = (1+2sinx+sin^2x) / cos^2x

To simplify the expression secx+tanx/secx-tanx, we can use the identities:

- secx = 1/cosx
- tanx = sinx/cosx

Substituting these values into the expression, we get:

(1/cosx + sinx/cosx) / (1/cosx - sinx/cosx)

Now, to simplify further, we can combine the fractions by multiplying the numerator and denominator of the big fraction by cosx. This yields:

((1 + sinx) * cosx) / ((1 - sinx) * cosx)

Now, we can divide cosx out in the numerator and denominator:

(1 + sinx) / (1 - sinx)

Next, let's simplify the right side of the equation. We can rewrite the expression 1 + 2sinx + sin^2x / cos^2x as:

(cos^2x + 2sinx*cosx + sin^2x) / cos^2x

Now, simplifying the numerator a bit, we have:

(1 + sinx)^2 / cos^2x

Using the identity sin^2x + cos^2x = 1, we can rewrite cos^2x as 1 - sin^2x:

(1 + sinx)^2 / (1 - sin^2x)

Applying the identity (a + b)^2 = a^2 + 2ab + b^2, we can expand (1 + sinx)^2:

(1 + 2sinx + sin^2x) / (1 - sin^2x)

Now, we can observe that the numerator and denominator of the right side are the same as in the previous expression.

Therefore, we've shown that the left side of the equation (secx+tanx/secx-tanx) is equal to the right side of the equation (1 + 2sinx + sin^2x / cos^2x).