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question:Find all the real solutions to [frac{(x 1)(x 2)(x 3)(x 4)(x 3)(x 2)(x 1)}{(x 2)(x 4)(x 2)} = 1.]Enter all the solutions, separated by commas.
answer:To find all the real solutions to the given equation, we start by examining the equation itself: [frac{(x - 1)(x - 2)(x - 3)(x - 4)(x - 3)(x - 2)(x - 1)}{(x - 2)(x - 4)(x - 2)} = 1.] First, we note that if x = 2 or x = 4, the denominator becomes zero, making the fraction undefined. Therefore, x neq 2 and x neq 4 for the equation to be valid. Given that x neq 2 and x neq 4, we can simplify the equation by canceling out the common factors in the numerator and the denominator: [(x - 1)(x - 3)(x - 3)(x - 1) = 1.] This simplifies further to: [(x - 1)^2 (x - 3)^2 = 1.] Rearranging the equation gives us: [(x - 1)^2 (x - 3)^2 - 1 = 0.] We can factor this equation using the difference of squares: [((x - 1)(x - 3) + 1)((x - 1)(x - 3) - 1) = 0.] We then solve for x in each factor: 1. For (x - 1)(x - 3) + 1 = 0, we get: [x^2 - 4x + 4 = 0,] which simplifies to: [(x - 2)^2 = 0.] However, we have already established that x neq 2. 2. For (x - 1)(x - 3) - 1 = 0, we get: [x^2 - 4x + 2 = 0.] Using the quadratic formula, x = frac{-b pm sqrt{b^2 - 4ac}}{2a}, where a = 1, b = -4, and c = 2, we find: [x = frac{4 pm sqrt{(-4)^2 - 4 cdot 1 cdot 2}}{2 cdot 1} = frac{4 pm sqrt{16 - 8}}{2} = frac{4 pm sqrt{8}}{2} = 2 pm sqrt{2}.] Therefore, the real solutions to the given equation are boxed{2 + sqrt{2}, 2 - sqrt{2}}.
question:There's only a week left before Christmas. John went out to buy gifts for his family. Having 999.00 for his budget, he went to a sports store to buy gifts for his brother, sister, and parents. He bought his brother a new pair of shoes for 165.00, a yoga mat for his sister which costs 85.00, a sports watch for his father at 215.00, and a set of hand weights for his mother for 60.00. In addition to the gift prices, there is a 7% sales tax on all items. Furthermore, there is a 10% discount on the sports watch. How much money does he have left after buying all the gifts, considering the discount and sales tax?
answer:First, let's calculate the total cost of the gifts before tax and discount: Brother's shoes: 165.00 Sister's yoga mat: 85.00 Father's sports watch: 215.00 Mother's hand weights: 60.00 Total cost before tax and discount = 165.00 + 85.00 + 215.00 + 60.00 Total cost before tax and discount = 525.00 Now, let's calculate the discount on the sports watch: Discount on sports watch = 10% of 215.00 Discount on sports watch = 0.10 * 215.00 Discount on sports watch = 21.50 Subtract the discount from the original price of the sports watch: Discounted price of sports watch = 215.00 - 21.50 Discounted price of sports watch = 193.50 Now, let's calculate the total cost of the gifts after the discount: Total cost after discount = 165.00 (shoes) + 85.00 (yoga mat) + 193.50 (discounted sports watch) + 60.00 (hand weights) Total cost after discount = 503.50 Next, we need to calculate the sales tax on the total cost after discount: Sales tax = 7% of 503.50 Sales tax = 0.07 * 503.50 Sales tax = 35.245 Since sales tax is usually rounded to the nearest cent, we'll round this to 35.25. Now, let's calculate the total cost including the sales tax: Total cost including tax = 503.50 + 35.25 Total cost including tax = 538.75 Finally, let's calculate how much money John has left after buying all the gifts: Money left = Initial budget - Total cost including tax Money left = 999.00 - 538.75 Money left = 460.25 John has boxed{460.25} left after buying all the gifts, considering the discount and sales tax.
question:What will be the result of 7 ^ 8 6 / 2 + 9 ^ 3 + 3 + some number if the result is 95?
answer:To find the value of "some number" that makes the expression equal to 95, we first need to calculate the value of the expression without "some number" and then solve for "some number". The expression is: 7 ^ 8 - 6 / 2 + 9 ^ 3 + 3 + some number First, we calculate the exponentiation: 7 ^ 8 = 7 * 7 * 7 * 7 * 7 * 7 * 7 * 7 = 5764801 9 ^ 3 = 9 * 9 * 9 = 729 Now, we calculate the division: 6 / 2 = 3 Now we can put it all together: 5764801 - 3 + 729 + 3 + some number Combine the constants: 5764801 + 729 + 3 - 3 = 5764801 + 729 = 5765530 Now we have: 5765530 + some number = 95 To find "some number", we subtract 5765530 from both sides of the equation: some number = 95 - 5765530 some number = -5765435 So, "some number" is boxed{-5765435} to make the result of the expression equal to 95.
question:Define a power cycle to be a set ( S ) consisting of the nonnegative integer powers of an integer ( a ), i.e. ( S = {1, a, a^2, ldots} ) for some integer ( a ). What is the minimum number of power cycles required such that given any odd integer ( n ), there exists some integer ( k ) in one of the power cycles such that ( n equiv k pmod{1024} )?
answer:To solve this problem, we need to show the minimum number of power cycles required so that any odd integer ( n ) modulo 1024 can be represented as some ( k ) in one of the power cycles ( S ). 1. Partitioning the Odd Residues Modulo 1024 First, we categorize the residues modulo 1024 into 10 classes: 1. **Class 1**: Residues congruent to ( mod 1) modulo 4. 2. **Classes 2 to 9**: For each ( n ) from 2 to 9, residues congruent to ( 2^n - 1 mod 2^{n+1} ): - Class 2: ( 2^2 - 1 mod 8 = 3 ) - Class 3: ( 2^3 - 1 mod 16 = 7 ) - Class 4: ( 2^4 - 1 mod 32 = 15 ) - Class 5: ( 2^5 - 1 mod 64 = 31 ) - Class 6: ( 2^6 - 1 mod 128 = 63 ) - Class 7: ( 2^7 - 1 mod 256 = 127 ) - Class 8: ( 2^8 - 1 mod 512 = 255 ) - Class 9: ( 2^9 - 1 mod 1024 = 511 ) 3. **Class 10**: ( -1 mod 1024 = 1023 ) If ( a ) is in class 1, then all elements of ( S_a ) are in class 1. If ( a ) is in class ( n ) for ( 2 leq n leq 9 ), then ( S_a ) includes elements from both class ( n ) and ( 1 mod 2^{n+1} ). If ( a ) is in class 10, ( S_a ) will include elements from both class 10 and ( 1 mod 1024 ). 2. Counting the Number of Required Cycles We observe that each class has unique elements that must be included in at least one cycle. Specifically: - Class 1 contains residues ( 1 mod 4 ). - Classes ( 2 ) through ( 9 ) contain, respectively, ( 7, 15, 31, 63, 127, 255, 511 ). - Class 10 contains ( 1023 . 3. Examining a Specific Power Cycle Consider the cycle generated by ( 5 ): - The order of 5 modulo 1024, which is the smallest positive power of 5 congruent to 1, is 256. - From ( 5^0, 5^1, ldots, 5^{255} ), no pair of values will be congruent modulo 1024, showing distinctness. Dividing this analysis for ( n ) from ( 2 ) to ( 9 ): - Let ( a = 2^n - 1 ) - The order of ( a ) modulo 1024 yields ( 2^{10 - n} ) Finally, ( S_{-1} ) contains elements congruent to the class 10 residue ( 1023 ). 4. Verifying the Coverage Now, let's verify: - ( S_5 ) contains at least 256 distinct elements covering all member residues in class 1. - ( S_{2^n-1} ) covers respective classes from 2 to 9. - ( S_{-1} ) covers class 10. Therefore, these cycles indeed cover all the residues mod 1024: - 1 class + 8 cycles for each ( n ) from 2 to 9 + 1 class for 10 = total 10 cycles. # Conclusion: The minimum number of power cycles required is: [ boxed{10} ]