Step-by-step explanation:
=(1+ sin^2 A/cos^2 A).cos^2 A
=[(cos^2 a+sin^2 a)/cos^2 a].cos^2 A
=[1/cos^2 a] . cos^2 a
=1
We'll assume this is an arbitrary triangle ABC.
A) No, the sines of two different angles can be whatever they want
B) sin(B)=cos(90-B)
Yes, that's always true. The "co" in cosine means "complementary" as in the complementary angle, which adds to 90. So the sine of an angle is the cosine of the complementary angle.
C) No, the correct identity is sin(180-B)=sin B. Supplementary angles share the same sine.
D) Just like A, different triangle angles often have different cosines.
Answer: Choice B
Answer:
A, B and E
Step-by-step explanation:
A proportional relationship has the form
y = kx ← k is the constant of proportionality
The only equations in this form are
A, B and E
Seventy- two thousand three hundred twelve
7+3x-12x=3x+1
We will first make all the numbers which have x in go to the left.
So 7+3x-12x-3x, we make the 3x negative since to make it move it needs to change.
Then we will make all the sevens go to the right, so 3x-12x-3x=1-7.
So now it is much easier to figure out.
-12x=-6
