Zusammenfassung der Ressource
Chapter 1
- Surds
- Simplifying
- Find something that can
be simplified
- sqrt(16)=4
- sqrt(25)=5
- Rationalising
- Simple
- Multiply by the root on
top and bottom
- sqrt(7) x sqrt(7) = 7
- Complex
- Multiply by the same
numbers with opposite
add/subtract sign
- 3+sqrt(7) x 3-sqrt(7) = 9+7 = 16
- Indices
- Rules of Indices
- Addition/Subtraction
- Factors with different indices do not combine by
addition or subtraction they stay separate.
- Division
- Subtract the indices
- e.g. 2^5 / 2^3 = 2^2 as 5-3 = 2.
- Multipication
- Add the indices
- e.g. 2^5 x 2^3 = 2^8 as 5+3 = 8
- Brackets
- Multiply the brackets
- e.g. (2^5)^3 = 2^15 as 5 x 3 = 15
- More Indices
- Negative Powers
- If power is negative, then flip
and make power positive
- e.g. 2x^-2 = 2/x^2
- Fractional Powers
- x^a/b = (brt(x))^a
- e.g. x^4/3 = (4rt(x))^3
- Equations
- When moving fractional powers,
flip but keep +- the same
- e.g. x^2/3 = 100 ==> x = 100^3/2
- Moving integer powers
- If positive, then make a root.
- e.g. x^3 = 100 => x = 3rt(100)
- If negative, then make into
fraction and cross-multiply.
- Moving fractional powers
- If positive, then make power.
- e.g. x^1/2 = 100 => x = 100^2
- If negative, the move over the
other side, and flip top and
bottom then simplify.
- e.g. x^-3/2 = 100 => x = 100^-2/3