For example, "i= 1" can be written below the symbol, and "n" can be written above it, which means that I in the following quadrature formula is added to n from 1.
That is, (1+d1/p1) (1+d2/p2) ... (1+dn/pn).
2. Greek letters:
① ∏ is the Greek letter, that is, the capitalized form of π, which mathematically means quadrature operation or direct product operation, and is similar to σ in form.
② Lowercase: π
In mathematics, pi is often mentioned. Pi, generally expressed by π, is a common mathematical constant in mathematics and physics. It is defined as the ratio of the circumference to the diameter of a circle. It is also equal to the ratio of the area of a circle to the square of its radius.
Accurate calculation of geometric shapes such as circle perimeter, circle area and sphere volume is the key value. In the analysis, π can be strictly defined as the smallest positive real number x satisfying sin(x) = 0.
Constant pi ≈3. 14 Preliminary calculation of Zu Chongzhi (China) 3. 14 15926
Extended data:
?
Mathematical permutation and combination symbols
c？ Number of combinations
A (or p)? number of permutations
n？ Total number of elements
r？ Number of elements participating in the selection
Factorial, such as 5! =5×4×3×2× 1= 120, specify 0! = 1
Half factorial (also called double factorial), for example, 7! ! =7×5×3× 1= 105, 10! ! = 10×8×6×4×2=3840
σ addition
Discrete mathematical symbol
Universal quantifier
Existential quantifier
├ determinant (formula can be proved by L)
Satisfier (formula is valid on e, and formula can be satisfied on e)
The negation of a proposition, such as the negation of a proposition is ﹁ P.
∧ "He" ("And") Operation of Proposition
The "disjunctive" ("or", "combinable or") operation of propositions
"Conditional" Operation of Proposition
"Double Condition" Operation of Proposition
p & lt= & gtq？ Equivalence relation between propositions p and q
p = & gtq？ Implication relation between proposition P and Q (P is a sufficient condition for Q, and Q is a necessary condition for P)
A* the dual formula of formula A, or the reciprocal of number theory (can also be written as
)
wff？ Combination formula
iff？ The only possibility is that
"NAND" operation of proposition ("NAND gate")
The nor operation of a proposition (nor gate)
□? The modal particle "inevitable"
The modal particle "may"
null set
Belong to (such as "A∈B", that is, "A belongs to B")
Do not belong to
Power set of P(A) set a
The number of points in set a
r？ =R○R [R
Baidu Encyclopedia-π (Greek alphabet)