secx - sinxtanx

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

I guess you could go further, recalling that sin and cos are complementary functions, and get

(1-sinx)/cosx
= (1-cos(90-x))/sin(90-x)
= tan((90-x)/2)
= tan(45 - x/2)

Oops -- my bad!

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

To simplify the expression sec(x) - sin(x)tan(x), we can use some trigonometric identities to rewrite it in a simpler form.

Step 1: Recall the definitions of sec(x) and tan(x):
sec(x) = 1/cos(x)
tan(x) = sin(x)/cos(x)

Step 2: Substitute the definitions of sec(x) and tan(x) into the expression:
sec(x) - sin(x)tan(x) = 1/cos(x) - sin(x) * (sin(x)/cos(x))

Step 3: Simplify the expression using the common denominator cos(x):
= 1/cos(x) - sin^2(x)/cos(x)

Step 4: Combine the fractions by finding a common denominator:
= (1 - sin^2(x))/cos(x)

Step 5: Apply the Pythagorean Identity sin^2(x) + cos^2(x) = 1:
= cos^2(x)/cos(x)

Step 6: Simplify and cancel out the cos(x) terms:
= cos(x)

Therefore, the simplified expression is cos(x).

To simplify the expression sec(x) - sin(x)tan(x), we can use trigonometric identities.

First, let's simplify the expression sin(x)tan(x):

tan(x) can be expressed as sin(x)/cos(x). So, sin(x)tan(x) = sin(x) * (sin(x)/cos(x)) = (sin^2(x))/cos(x).

Now, the expression becomes sec(x) - (sin^2(x))/cos(x).

Next, let's simplify the expression sec(x):

Using the reciprocal identity, sec(x) = 1/cos(x).

So, the expression now becomes 1/cos(x) - (sin^2(x))/cos(x).

To combine these fractions, multiply the first fraction by cos(x)/cos(x) and the second fraction by 1/1:

(1 * cos(x))/(cos(x) * cos(x)) - (sin^2(x))/cos(x).

Simplifying further:

= cos(x)/cos^2(x) - (sin^2(x))/cos(x).

Now, let's simplify the numerator:

cos(x)/cos^2(x) = 1/cos(x).

Finally, we have:

1/cos(x) - (sin^2(x))/cos(x) = (1 - sin^2(x))/cos(x).

The simplified expression is (1 - sin^2(x))/cos(x), which can be further simplified to cos^2(x)/cos(x) = cos(x).