来自社区的分享

解题库

浏览清晰、完整的数学解答,覆盖不同难度。

共 550 个公开解答

Algebra

2024年11月3日

The solution to the equation involving radicals and exponents is x = 77/120.

Word-Problem

2024年11月3日

The water lily takes 47 days to cover half the pond, given that it doubles in size each day and covers the entire pond on day 48.

Algebra

2024年10月31日

The equation 3^(x^2)/9^x = 81 is solved by rewriting the equation with the same base, simplifying the denominator, applying the quotient rule for exponents, equating the exponents, rearranging into a quadratic equation, and finally using the quadratic formula to find the two solutions, x = 1 + √5 and x = 1 - √5.

Algebra

2024年10月31日

The equation x^2 + 3x + 7 = 6/(x^2 + 3x + 2) is solved by substituting u = x^2 + 3x, resulting in a quadratic equation in u. Factoring the quadratic equation yields two possible values for u, which are then substituted back into the substitution to find the solutions for x using the quadratic formula. One case results in two real solutions, while the other yields no real solutions.

Algebra

2024年10月30日

The solution to the equation \sqrt{7 + \frac{3}{\sqrt{x}}} = 7 - \frac{9}{x} is x = \frac{9}{4}.

Algebra

2024年10月29日

The solution demonstrates how to find the value of RS by expanding the second equation, substituting the first equation, and simplifying the resulting equation.

Algebra

2024年10月29日

The solution for X in the equation 2^X + 2 = 66 is 6.

Pre-Algebra

2024年10月28日

To solve for a in the equation (a/2) ÷ (5/2) = 2, first rewrite the division as multiplication by the reciprocal, then multiply the numerators and denominators, simplify the fraction, isolate a by multiplying both sides by 10, and finally solve for a by dividing both sides by 2, resulting in a = 10.

Algebra

2024年10月28日

To solve the equation 16/x = x^2/4, cross-multiply to get 64 = x^3, then take the cube root of both sides to find x = 4.

Algebra

2024年10月28日

The solution to the equation (1/3)^(x+3) = 9^x is x = -1.

Calculus

2024年10月27日

The inverse Laplace transform of 1/x^(3/2) is 2/(sqrt(pi))*sqrt(x).

Calculus

2024年10月27日

The Laplace transform of sin^2(t) is 2 / (s * (s^2 + 4)).

Calculus

2024年10月27日

The Laplace transform of e^(t/2) is 1/(s - 1/2), provided s > 1/2.

Algebra

2024年10月27日

The equation |a - 5| = |5 - a| is proven by considering two cases: when (a - 5) is greater than or equal to zero and when (a - 5) is less than zero. In both cases, the equation holds true, demonstrating that the absolute value of the difference between a and 5 is equal to the absolute value of the difference between 5 and a for all values of a.

Algebra

2024年10月27日

The rational function 1/(3x^2 + 4x + 1) is decomposed into partial fractions as (3/2)/(3x + 1) - (1/2)/(x + 1) by factoring the denominator and solving for the unknown constants using strategic values of x.

Algebra

2024年10月27日

The partial fraction decomposition of the rational expression x/((x+1)(x-4)) is (1/5)/(x+1) + (4/5)/(x-4).

Geometry

2024年10月26日

The area of the region defined by the inequalities y ≥ x, y > -x + 1, and y < 10 is 90.25 square units.

Algebra

2024年10月26日

The system of equations is solved by substitution, expanding, simplifying, using the quadratic formula to find x values, and then substituting back into the equations to find the corresponding y values. The solutions are (3, 4) and (-4, -3).

Algebra

2024年10月26日

The solution to the system of equations x + 2y = 5 and 3x - y = 1 is x = 1 and y = 2, found using the elimination method.

Algebra

2024年10月24日

The solution for x in the equation involving fractions with (x-1) and (x+1) in the denominator is x = √2 and x = -√2.

Algebra

2024年10月23日

The solution to the equation 3^(a^2 - 10a + 25)! = 729^4 is a = 3 or a = 7, found by equating exponents after expressing both sides with the same base and solving the resulting quadratic equation.

Pre-Algebra

2024年10月22日

To find the difference between ba and ab, where a and b are digits, we analyze the units and hundreds digits, leading to the conclusion that the hundreds digit of the difference is 3.

Algebra

2024年10月22日

The solution to the equation 4a³ = 2⁵ is a = 2.

Algebra

2024年10月22日

The equation was solved by simplifying the square root, isolating the square root term, squaring both sides, moving all terms to one side, factoring out a common factor, and solving for x, resulting in two solutions: x = 0 and x = 16/81.

Algebra

2024年10月21日

The solution to the equation 3^x = 1 and 3^y = 81 is x + y = 4.

Algebra

2024年10月21日

By solving the system of equations x + y = 3 and x - y = 9, we find x = 6 and y = -3. Then, substituting these values into (x/y)^2, we get 4.

Calculus

2024年10月21日

The total volume of infinitely many cubes with side lengths decreasing according to the sequence 1, 1/√2, 1/√3, ... is finite, while the total surface area is infinite.

Algebra

2024年10月21日

The expression 2^(n+4) - 2(2^n) / 2(2^(n+3)) simplifies to 7/8.

Calculus

2024年10月20日

The derivative of xy + sin(x) = e^y with respect to x is found using implicit differentiation, applying the product rule and chain rule, and solving for dy/dx.

Calculus

2024年10月20日

The derivative of x² + y² = 25 with respect to x is -x/y.

«»