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❓Find the distance between the points (0, 6) and (8, 0) and calculate the area of the triangle formed by these points and the origin (0,0).
💡To find the distance between the points (0, 6) and (8, 0), I will use the distance formula. The distance formula is derived from the Pythagorean theorem and allows me to calculate the straight-line distance between two points in a coordinate plane.First, I identify the coordinates of the two points:- Point A: (0, 6)- Point B: (8, 0)The distance formula is:[text{Distance} = sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}]Substituting the coordinates into the formula:[text{Distance} = sqrt{(8 - 0)^2 + (0 - 6)^2} = sqrt{8^2 + (-6)^2} = sqrt{64 + 36} = sqrt{100} = 10]Next, to calculate the area of the triangle formed by the points (0, 6), (8, 0), and the origin (0, 0), I can use the formula for the area of a triangle with vertices at (0, 0), (x1, y1), and (x2, y2):[text{Area} = frac{1}{2} |x1 times y2 - x2 times y1|]Substituting the coordinates:[text{Area} = frac{1}{2} |0 times 0 - 8 times 6| = frac{1}{2} |0 - 48| = frac{1}{2} times 48 = 24]Therefore, the distance between the points is 10 units, and the area of the triangle is 24 square units.
❓If some ounces of a strong vinegar solution are diluted with 50 ounces of water to form a 7 - percent vinegar solution, and the concentration of the original solution was 36.166666666666664 percent. How many ounces of the original vinegar solution were used?
💡First, I need to determine the amount of the original vinegar solution that was diluted with 50 ounces of water to create a 7% vinegar solution. The original solution has a concentration of 36.166666666666664%.Let’s denote the amount of the original solution as ( x ) ounces.The amount of pure vinegar in the original solution is ( 0.3616666666666664 times x ) ounces.After dilution, the total volume of the solution becomes ( x + 50 ) ounces, and the concentration is 7%, so the amount of pure vinegar in the diluted solution is ( 0.07 times (x + 50) ) ounces.Since the amount of pure vinegar remains the same before and after dilution, I can set up the equation:[0.3616666666666664 times x = 0.07 times (x + 50)]Solving for ( x ):[0.3616666666666664x = 0.07x + 3.5]Subtract ( 0.07x ) from both sides:[0.2916666666666664x = 3.5]Divide both sides by ( 0.2916666666666664 ):[x approx 12]Therefore, approximately 12 ounces of the original vinegar solution were used.
❓The negation of the proposition "forall xin R, e^{x}geqslant x+1" is:A: forall xin R, e^{x} lt x+1B: exists x_{0}in R, e^{x_{0}}geqslant x_{0}+1C: forall xnotin R, e^{x} lt x+1D: exists x_{0}in R, e^{x_{0}} lt x_{0}+1
💡Okay, so I have this problem here about negating a proposition involving a universal quantifier and an inequality. The proposition is: "For all x in real numbers, e raised to the power of x is greater than or equal to x plus one." And I need to find its negation from the given options.First, I remember that negating a statement in logic involves flipping the quantifiers and the inequalities. So, if the original statement is a universal quantifier saying something is true for all x, the negation should be an existential quantifier saying that there exists at least one x where the opposite is true.So, the original statement is: ∀x∈ℝ, e^x ≥ x + 1.To negate this, I should change the "for all" (∀) to "there exists" (∃), and then negate the inequality. The inequality here is "greater than or equal to," so its negation should be "less than."Putting that together, the negation should be: ∃x∈ℝ, e^x < x + 1.Now, looking at the options provided:A: ∀x∈ℝ, e^x < x + 1 B: ∃x₀∈ℝ, e^{x₀} ≥ x₀ + 1 C: ∀x∉ℝ, e^x < x + 1 D: ∃x₀∈ℝ, e^{x₀} < x₀ + 1Option A is still a universal quantifier, which isn't correct because the negation should be existential. Option B uses the same inequality as the original statement, just with an existential quantifier, so that's not the negation. Option C talks about x not in ℝ, which doesn't make sense because the original statement was about all real numbers, so the negation should still be within the real numbers. Option D matches what I came up with: an existential quantifier and the inequality flipped to "less than."So, I think the correct answer is D.But wait, let me double-check. If the original statement is that e^x is always at least x + 1 for every real number x, then the negation would be that there is at least one real number x where e^x is less than x + 1. That makes sense because if even one such x exists, the original statement isn't true for all x.Yeah, I'm pretty confident now that D is the correct negation.
❓What is the probability that the sum of two non-standard dice, with one having 8 sides (faces numbered 1, 2, 3, 4, 5, 6, 7, 8) and the other having 10 sides (faces numbered 1, 2, 3, 4, 5, 6, 7, 8, 9, 10), will yield a sum of 11, and then when both are thrown again, their sum will once more yield an 11? Calculate the probability of obtaining this specific sum for two consecutive throws.
💡First, I need to determine the total number of possible outcomes when rolling an 8-sided die and a 10-sided die. This is calculated by multiplying the number of sides on each die, which gives 8 × 10 = 80 possible outcomes.Next, I'll identify all the combinations of rolls that result in a sum of 11. By listing the possible pairs where the sum equals 11, I find there are 8 such combinations.With the number of successful outcomes known, I can calculate the probability of rolling a sum of 11 on a single throw by dividing the number of successful outcomes by the total number of possible outcomes: 8/80 = 1/10.Since the two throws are independent events, the probability of rolling a sum of 11 on both throws is the product of the probabilities of each individual event: (1/10) × (1/10) = 1/100.Finally, converting this fraction to a decimal gives a probability of 0.01, which is equivalent to 1%.
❓Let g(n) =tfrac{1}{4} n(n+1)(n+2)(n+3). Find the expression for g(r)-g(r-1).A) 4r(r+1)(r+2)B) (r+1)(r+2)(r+3)C) r(r+1)(r-1)D) r(r+1)(r+2)
💡Okay, so I need to find the expression for ( g(r) - g(r-1) ) where ( g(n) = frac{1}{4} n(n+1)(n+2)(n+3) ). Hmm, let me break this down step by step. First, I should write out what ( g(r) ) and ( g(r-1) ) are individually. Starting with ( g(r) ):[g(r) = frac{1}{4} r(r+1)(r+2)(r+3)]That looks straightforward. Now, for ( g(r-1) ), I need to substitute ( r-1 ) in place of ( n ) in the original function:[g(r-1) = frac{1}{4} (r-1)r(r+1)(r+2)]Okay, so now I have both ( g(r) ) and ( g(r-1) ). The next step is to subtract ( g(r-1) ) from ( g(r) ):[g(r) - g(r-1) = frac{1}{4} r(r+1)(r+2)(r+3) - frac{1}{4} (r-1)r(r+1)(r+2)]Hmm, both terms have a common factor of ( frac{1}{4} r(r+1)(r+2) ). Maybe I can factor that out to simplify the expression. Let me try that:[g(r) - g(r-1) = frac{1}{4} r(r+1)(r+2) left[ (r+3) - (r-1) right]]Now, simplifying inside the brackets:[(r+3) - (r-1) = r + 3 - r + 1 = 4]So, plugging that back in:[g(r) - g(r-1) = frac{1}{4} r(r+1)(r+2) times 4]The ( frac{1}{4} ) and the 4 cancel each other out, leaving:[g(r) - g(r-1) = r(r+1)(r+2)]Let me double-check my steps to make sure I didn't make a mistake. I factored out the common terms correctly, and the subtraction inside the brackets simplified to 4, which then canceled with the ( frac{1}{4} ). So, it seems like the final expression is indeed ( r(r+1)(r+2) ).Looking at the options provided:A) (4r(r+1)(r+2))B) ((r+1)(r+2)(r+3))C) (r(r+1)(r-1))D) (r(r+1)(r+2))The expression I found matches option D. So, I think the correct answer is D.**Final Answer**boxed{D}
❓The father is 5 times Taehyung's age, and the mother is 4 times Taehyung's age. If Taehyung is 9 years old, how many years younger is his mother than his father?
💡First, I recognize that Taehyung is 9 years old.Next, I calculate the father's age by multiplying Taehyung's age by 5:5 × 9 = 45 years.Then, I calculate the mother's age by multiplying Taehyung's age by 4:4 × 9 = 36 years.Finally, to find out how many years younger the mother is than the father, I subtract the mother's age from the father's age:45 years - 36 years = 9 years.