Hello,
y=sin²(cos(2x))
y'=2*sin(cos(2x))*cos(cos(2x))*(-sin(2x)*2)
= -4*sin(cos(2x))*cos(cos(2x))*sin(2x)
Let's solve for x.
x
+
4
y
=
(
14
)
(
3
)
x
+
7
y
Step 1: Add -42x to both sides.
x
+
4
y
+
−
42
x
=
42
x
+
7
y
+
−
42
x
−
41
x
+
4
y
=
7
y
Step 2: Add -4y to both sides.
−
41
x
+
4
y
+
−
4
y
=
7
y
+
−
4
y
−
41
x
=
3
y
Step 3: Divide both sides by -41.
−
41
x
−
41
=
3
y
−
41
x
=
−
3
41
y
Answer:
x
=
−
3
41
y
Call the number : x
(1/3)x + 5 = x-6
=> (1/3)x + 5 - (x-6) = 0
=> (1/3)x + 5 - x + 6 = 0
Group (1/3)x with -x, 5 with 6
=> [(1/3)x - x] + (5+6) = 0
=> (-2/3)x + 11 = 0
=> (-2/3)x = -11
=> x = -11 : (-2/3) = 33/2.
Recheck : 1/3 x 33/2 + 5 = 33/6 + 5 = 63/6 = 21/2
33/2 - 21/2 = 12/2 = 6 (21/2 is 6 less than 33/2, satisfied.)
How to solve with elimination: with the equations on the top, add the number on top and bottom if they share a variable such as x. do the rest for all of the numbers.
35 + 3n= x
x being the total amount of stamps!
is there a substitution for n? or a number of months?
