simplify the expression by using a double angle formula or a half angle formula:

a. 2 tan 7 degrees /1-tan^2 7 degrees

b.2 tan 7 theta / 1-tan^2 7 theta

recall that tan(2x) = 2tanx/(1-tan^2 x)

To simplify the expression in part a, we can utilize the double angle formula for tangent:

tan(2θ) = 2tan(θ) / (1 - tan^2(θ))

Comparing this formula to the expression given:

2tan(7 degrees) / (1 - tan^2(7 degrees))

We can see that the expression matches the double angle formula, with θ being equal to 7 degrees. Therefore, we can substitute θ = 7 degrees into the formula to simplify the expression:

2tan(7 degrees) / (1 - tan^2(7 degrees)) = tan(2 * 7 degrees) = tan(14 degrees)

So, the expression simplifies to tan(14 degrees).

Now let's simplify the expression in part b. Similar to part a, we can use the double angle formula for tangent:

tan(2θ) = 2tan(θ) / (1 - tan^2(θ))

Comparing it to the given expression:

2tan(7θ) / (1 - tan^2(7θ))

We can substitute θ = 7θ into the formula to simplify the expression:

2tan(7θ) / (1 - tan^2(7θ)) = tan(2 * 7θ) = tan(14θ)

So, the expression simplifies to tan(14θ).