Powers, Roots & Standard Form (Edexcel IGCSE Maths A)

Flashcards

1/20

Enjoying Flashcards?
Tell us what you think

Cards in this collection (20)

  • What number do you get when you raise any non-zero number to the power of zero?

    Any non-zero number raised to the power of 0 is equal to 1.

  • What is a square root of a number?

    A square root of a number is a value that, when squared, gives the original number.

  • True or False?

    Every positive number has two square roots.

    True.

    Every positive number has two square roots, one positive and one negative.

  • What function does the symbol square root of blank end root refer to when applied to a positive number?

    square root of blank end root refers to the positive square root of a positive number.

    For example, square root of 9 equals 3.

  • True or False?

    Cube roots of negative numbers do not exist.

    False.

    The cube root of a negative number will also be a negative number.

    For example, -5 is a cube root of -125.

  • Define the term reciprocal.

    The reciprocal of a number is the number that you multiply it by to get 1.

    For example, 2 over 3 is the reciprocal of 3 over 2.

  • What do you get if you raise a non-zero number to the power of -1?

    If you raise a non-zero number to the power of -1 you get the reciprocal of the number.

    E.g. 3 to the power of negative 1 end exponent equals 1 third

  • What do you get if you raise a positive number to the power of ½?

    If you raise a non-zero number to the power of ½ you get its positive square root.

    E.g. 5 to the power of 1 half end exponent equals square root of 5

  • What is the index law for a to the power of m cross times a to the power of n?

    a to the power of m cross times a to the power of n equals a to the power of m plus n end exponent.

    If you multiply two powers with the same base number, you add the indices together.

  • What is the index law for a to the power of m divided by a to the power of n?

    a to the power of m divided by a to the power of n equals a to the power of m minus n end exponent.

    If you divide two powers with the same base number, you subtract one index from the other.

  • What is the index law for open parentheses a to the power of m close parentheses to the power of n?

    open parentheses a to the power of m close parentheses to the power of n equals a to the power of m cross times n end exponent.

    If you raise a power to another power, you multiply the indices.

  • True or False?

    a to the power of m over n end exponent equals open parentheses m-th root of a to the power of n end root close parentheses

    False.

    a to the power of m over n end exponent equals open parentheses n-th root of a close parentheses to the power of m. The denominator of an index is the root and the numerator of an index is the power.

  • What does a number written in standard form look like?

    A number in standard form looks like a cross times 10 to the power of n. A number between 1 and 10 multiplied by a power of ten.

  • When a number is written in standard form a cross times 10 to the power of n, which values can a be?

    For a cross times 10 to the power of n, a is at least 1 and less than 10, 1 less or equal than a less than 10. This means there is one non-zero digit before the decimal point.

  • When a value between 0 and 1 is written in standard form a cross times 10 to the power of n, what type of number will n be?

    If a value is between 0 and 1 then when it is written in standard form, n will be a negative number.

  • When a number is written in standard form a cross times 10 to the power of n, what type of number can n be?

    For a cross times 10 to the power of n, the value n must be an integer. It can be zero, positive or negative.

  • How do you multiply two numbers that are written in standard form and give the answer in standard form without a calculator?

    Multiply together the values of a from both numbers and write this in standard form if needed.

    Add together the indices for the powers of 10 from each number.

    Multiply the two parts together. Simplify if necessary

  • How do you divide two numbers that are written in standard form and give the answer in standard form without a calculator?

    Divide the values of a for both numbers and write this in standard form if needed.

    Subtract the indices for the powers of 10 for both numbers.

    Multiply the two parts together. Simplify if necessary

  • How do you add two numbers that are written in standard form and give the answer in standard form without a calculator?

    Rewrite the smaller number so that it has the same power as the larger number.

    Add the values of a.

    If a is bigger than 10 then divide it by 10 and increase the power of 10 by 1.

  • How do you subtract two numbers that are written in standard form and give the answer in standard form without a calculator?

    Rewrite the smaller number so that it has the same power as the larger number.

    Subtract the values of a.

    If a is less than 1 then multiply it by 10 and decrease the power of 10 by 1.