<u>Answer:</u>
The basic identity used is 
.
<u>Solution:
</u>
In this problem some of the basic trigonometric identities are used to prove the given expression.
Let’s first take the LHS:
Step one:
The sum of squares of Sine and Cosine is 1 which is:
On substituting the above identity in the given expression, we get,
Step two:
The reciprocal of cosine is secant which is:
On substituting the above identity in equation (1), we get,
Thus, RHS is obtained.
Using the identity , the given expression is verified.
Answer:
I can not see the question please put it in the comments of this and I will further help you! Sorry I have terrible vision!
Step-by-step explanation:
Since it is shown that 2 of the sides of the triangle are congruent, we can assume that they have the same angle measures.
so to solve for the missing angle you can set up an equation equal to 180 since all triangles add up to 180 degrees.
21 + 21 + x = 180
42 + x = 180
x = 138
the value of the missing angle should be 138 degrees
hope this helped
I and 4i
let's say if you have i you can automatically think there is a one in front of it so one term like this (i) could look like this 1i and any number with the same variable or letter are like terms
hope this helps
