How do you calculate something like $9^{21}$ in your head quickly? Was asked this during an interview and did not know what is a good way to quickly derive the answer. The actual answer is $1.0941899\times10^{20}$.
2026-03-25 20:58:01.1774472281
How to quickly mentally calculate large powers for a single digit?
79 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in EXPONENTIATION
- exponential equation with different bases; no logarithms
- Is square root of $y^2$ for every $y>0,y\in\mathbb{R}$?
- Definite sum for $(1+a)^n$
- Fractional exponents definition and the additive law of exponents
- Fourth term in the expansion of $(1-2x)^{3/2}$
- Why is $\int_{0}^{t} e^{nt} \mathrm{\ dt} = \frac{1}{n} \left(e^{nt} - 1\right)$? [solved; notation is also faulty in the first place]
- Exponentiation property of the modulo operator
- When are $\left(\frac{a}{b}\right)^c$ and $\frac{a^c}{b^c}$ equivalent?
- How can I rewrite expression to get log out of exponent
- Compare $2^{2016}$ and $10^{605}$ without a calculator
Related Questions in MENTAL-ARITHMETIC
- Multiplication tables: up to what number should I memorise?
- How to find a volume of this figure (which is $3080 \text{ cm}^3$) in a few seconds?
- How many zeros will $ 3^{3}4^{4}5^{5}6^{6} - 3^{6}4^{5}5^{4}6^{3}$ ends with?
- Generating "random" mental calculation exercises?
- Age questions: How to approach solving this?
- Vinculum number of 989?
- What method for mentally computing 2-digit multiplication problems, minimizes the amount of mental steps?
- Mental approximations of 1) log, 2) non-integer power
- What would be the best way to memorize the 10 by 10 multiplication table?
- Estimating square numbers
Trending Questions
- Induction on the number of equations
- How to convince a math teacher of this simple and obvious fact?
- Find $E[XY|Y+Z=1 ]$
- Refuting the Anti-Cantor Cranks
- What are imaginary numbers?
- Determine the adjoint of $\tilde Q(x)$ for $\tilde Q(x)u:=(Qu)(x)$ where $Q:U→L^2(Ω,ℝ^d$ is a Hilbert-Schmidt operator and $U$ is a Hilbert space
- Why does this innovative method of subtraction from a third grader always work?
- How do we know that the number $1$ is not equal to the number $-1$?
- What are the Implications of having VΩ as a model for a theory?
- Defining a Galois Field based on primitive element versus polynomial?
- Can't find the relationship between two columns of numbers. Please Help
- Is computer science a branch of mathematics?
- Is there a bijection of $\mathbb{R}^n$ with itself such that the forward map is connected but the inverse is not?
- Identification of a quadrilateral as a trapezoid, rectangle, or square
- Generator of inertia group in function field extension
Popular # Hahtags
second-order-logic
numerical-methods
puzzle
logic
probability
number-theory
winding-number
real-analysis
integration
calculus
complex-analysis
sequences-and-series
proof-writing
set-theory
functions
homotopy-theory
elementary-number-theory
ordinary-differential-equations
circles
derivatives
game-theory
definite-integrals
elementary-set-theory
limits
multivariable-calculus
geometry
algebraic-number-theory
proof-verification
partial-derivative
algebra-precalculus
Popular Questions
- What is the integral of 1/x?
- How many squares actually ARE in this picture? Is this a trick question with no right answer?
- Is a matrix multiplied with its transpose something special?
- What is the difference between independent and mutually exclusive events?
- Visually stunning math concepts which are easy to explain
- taylor series of $\ln(1+x)$?
- How to tell if a set of vectors spans a space?
- Calculus question taking derivative to find horizontal tangent line
- How to determine if a function is one-to-one?
- Determine if vectors are linearly independent
- What does it mean to have a determinant equal to zero?
- Is this Batman equation for real?
- How to find perpendicular vector to another vector?
- How to find mean and median from histogram
- How many sides does a circle have?