Answer:
3
Step-by-step explanation:
step1 Isolate the square root on the left hand side
Original equation
√2x-5-4 = -x
Isolate
√2x-5 = 4-x
step2 eliminate the radical on the left hand side
Raise both sides to the second power
(√2x-5)2 = (4-x)2
After squaring
2x-5 = x2-8x+16
step3 Solve the quadratic equation
Rearranged equation
x2 - 10x + 21 = 0
This equation has two rational roots:
{x1, x2}={7, 3}
step4 Check that the first solution is correct
Original equation, root isolated
√2x-5 = 4-x
Plug in 7 for x
√2•(7)-5 = 4-(7)
Simplify
√9 = -3
Solution does not check
3 ≠ -3
step5 Check that the second solution is correct
Original equation, root isolated
√2x-5 = 4-x
Plug in 3 for x
√2•(3)-5 = 4-(3)
Simplify
√1 = 1
Solution checks !!
Solution is:
x = 3
Answer: To find the inverse of the function, we need to make x as a function of y and at the final step make a switch between x and y (i.e. make x as y and y as x)
y = x² + 4x + 4 ⇒⇒⇒ factor the quadratic equation
y = (x+2)(x+2)
y = (x+2)² ⇒⇒⇒ take the square root to both sides
√y = x+2
x = √y - 2 ⇒⇒⇒ x becomes a function of y
final step:
∴ y = √x - 2 ⇒⇒⇒ the inverse of the given function
So, as a conclusion:
f(x) = y = x² + 4x + 4 ⇒⇒⇒ the given function
f⁻¹(x) = y = √x - 2 ⇒⇒⇒ the inverse of the given function
Answer: The probability is 1/8
Explanation:
Probability is a ratio of the number of relevant outcomes and total number of possible outcomes.
We are flipping the coin three times.
The number of relevant outcomes is 1 (one triple {Head, Head, Tail})
The number of all possible outcomes is the product of 2 possibilities (Head or Tail) on first toss, times another 2 on second, times another 2 on third, so 2^3 = 8.
The probability P = 1/8
Most likely you are expected to recognize that side lengths 2, 3, 5 will result in a "triangle" of zero area (looks like a line segment).
The appropriate choice is
(5, 3, 2)
_____
Some authors write the triangle inequality as a + b ≥ c for any assignment of a, b, c to side lengths. The "or equal to ..." allows the triangle to have zero area (looks like a line segment). Other authors insist the inequality not include the "or equal to" case. It looks like your text's author is in the latter camp.
