Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identity
sin²x + cos²x = 1 , then
sin²x = 1 - cos²x and cos²x = 1 - sin²x
Consider the left side
← expand numerator/denominator using FOIL
=
=
=
=
= cot²A = right side , thus proven
Answer:
See explanation below
Step-by-step explanation:
Find the value of x in each of the following
1) x-1+5√x-1+3=0
5√x-1 = -x -2
Square both sides
25(x-1) = (-x-2)^2
25(x-1) = x^2+4x + 4
25x-25 = x^2+4x + 4
x^2 +4x + 4 - 25x + 25 = 0
x^2 - 21x + 29 = 0
x = 21±√21²-4(29)/2
x = 21±√441-116/2
x = 21±√325/2
x = 21±18.03/2
x = 21+18.03/2 and 21-18.03/2
x = 19.515 and 1.485
4) x^4-64=0
x^4 = 64
x = 2.83