the assumption being that "x" is a plain variable whilst "y" is a function, that matters because the chain rule would be needed for a function, not so for a plain variable.

now, we know that y(5) = -23, which is another way of saying that when x = 5, y = -23, but we already knew that, we can get that by simply plugging it into the equation hmmm y'(5), well

Answer:
f(x) = 8(x-3)
Step-by-step explanation:
F^ -1 ( x) = x/8 +3
Let y = x/8+3
To find the inverse
Exchange x and y
x = y/8+3
Solve for y
x-3 = y/8+3-3
x-3 = y/8
Multiply each side by 8
8(x-3) = y/8 * 8
8(x-3) = y
The inverse of the inverse is the function so
f(x) = 8(x-3)
Answer:
(-4, 2), (-1, -3), (2,0), (4,3).
Answer:
Step-by-step explanation:
in tri ADC and tri BDC
∠ADC =∠BDC = 90
DC is common
AD = BD (given)
triangle ADC ≅ tri BDC by SAS congruency
hence AC = BC by CPCT ( congruent parts of congruent triangles)
hence, BC = 13
Answer:
see explanation
Step-by-step explanation:
(a)
x² + 2x + 1 = 2x² - 2 ( subtract x² + 2x + 1 from both sides
0 = x² - 2x - 3 ← in standard form
0 = (x - 3)(x + 1) ← in factored form
Equate each factor to zero and solve for x
x + 1 = 0 ⇒ x = - 1
x - 3 = 0 ⇒ x = 3
-----------------------------------
(b)
-
=
( multiply through by 15 to clear the fractions )
5(x + 2) - 2 = 3(x - 2) ← distribute parenthesis on both sides
5x + 10 - 2 = 3x - 6
5x + 8 = 3x - 6 ( subtract 3x from both sides )
2x + 8 = - 6 ( subtract 8 from both sides )
2x = - 14 ( divide both sides by 2 )
x = - 7
--------------------------------------------
(c) Assuming lg means log then using the rules of logarithms
log
⇔ nlogx
log x = log y ⇒ x = y
Given
log(2x + 3) = 2logx
log(2x + 3) = log x² , so
x² = 2x + 3 ( subtract 2x + 3 from both sides )
x² - 2x - 3 = 0
(x - 3)(x + 1) = 0
x = 3 , x = - 1
x > 0 then x = 3