1. It's a little tricky one🤔, Let √5 is a rational number. Therefore, we can find two integers a, b (b ≠ 0) such that √5 = a/b Let a and b have a common factor other than 1. Then we can divide them by the common factor, and assume that a and b are co-prime. a = √5b ⇒ a² = 5b² Therefore, a² is divisibleRead more

    It’s a little tricky one🤔,

    Let √5 is a rational number.
    Therefore, we can find two integers a, b (b ≠ 0) such that √5 = a/b Let a and b have a common factor other than 1. Then we can divide them by the common factor, and assume that a and b are co-prime.
    a = √5b
    ⇒ a² = 5b²
    Therefore, a² is divisible by 5 and it can be said that a is divisible by 5.
    Let a = 5k, where k is an integer
    (5k)² = 5b²
    ⇒ 5k² = b²
    This means that b² is divisible by 5 and hence, b is divisible by 5.
    This implies that a and b have 5 as a common factor.
    And this is a contradiction to the fact that a and b are co-prime.
    Hence, √5 cannot be expressed as p/q or it can be said that √5 is irrational.

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  2. Let 3+2√5 is rational. Therefore, we can find two co-prime integers a, b (b ≠ 0) such that 3+2√5 = a/b 2√5 = (a/b)-3 √5 = 1/2((a/b) - 3) Since a andbare integers, 1/2((a/b) - 3) will also be rational and therefore, √5 is rational. This contradicts the fact that √5 is irrational. Hence, our assumptioRead more

    Let 3+2√5 is rational.
    Therefore, we can find two co-prime integers a, b (b ≠ 0) such that
    3+2√5 = a/b
    2√5 = (a/b)-3
    √5 = 1/2((a/b) – 3)
    Since a andbare integers, 1/2((a/b) – 3) will also be rational and therefore, √5 is rational.
    This contradicts the fact that √5 is irrational. Hence, our assumption that 3 + 2√5 is rational is false. Therefore, 3 +2√5 is irrational.

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  3. Let 1/√2 is rational. Therefore, we can find two co-prime integers a, b (b ≠ 0) such that 1/√2 = a/b Or √2 = b/a b/a is as a and b are integers. Therefore, √2 is rational which contradicts to the fact that √2 is irrational. Hence, our assumption is false and 1/√2 is irrational. Video Explanation😀

    Let 1/√2 is rational.
    Therefore, we can find two co-prime integers a, b (b ≠ 0) such that
    1/√2 = a/b
    Or
    √2 = b/a
    b/a is as a and b are integers.
    Therefore, √2 is rational which contradicts to the fact that √2 is irrational.
    Hence, our assumption is false and 1/√2 is irrational.

    Video Explanation😀

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  4. Let 7√5 is rational. Therefore, we can find two co-prime integers a, b (b ≠ 0) such that 7√5 = a/b ⇒ √5 = a/7b a/7b is rational as a and b are integers. Therefore, √5 should be rational. This contradicts the fact that √5 is irrational. Therefore, our assumption that 7√5 is rational is false. Hence,Read more

    Let 7√5 is rational.
    Therefore, we can find two co-prime integers a, b (b ≠ 0) such that
    7√5 = a/b
    ⇒ √5 = a/7b
    a/7b is rational as a and b are integers.
    Therefore, √5 should be rational.
    This contradicts the fact that √5 is irrational. Therefore, our assumption that 7√5 is rational is false. Hence, 7√5 is irrational.

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  5. I can Solve this question😁, If any number ends with the digit 0, it should be divisible by 10 or in other words, it will also be divisible by 2 and 5 as 10 = 2 × 5. Prime factorisation of 6ⁿ = (2 × 3)ⁿ According to Fundamental Theorem of Arithmetic, the factorisation is uniqe. It can be observed thaRead more

    I can Solve this question😁,

    If any number ends with the digit 0, it should be divisible by 10 or in other words, it will also be divisible by 2 and 5 as 10 = 2 × 5.
    Prime factorisation of 6ⁿ = (2 × 3)ⁿ
    According to Fundamental Theorem of Arithmetic, the factorisation is uniqe. It can be observed that 5 is not in the prime factorisation of 6ⁿ.
    Hence, for any value of n, 6n will not be divisible by 5. Therefore, 6n cannot end with the digit 0 for any natural number n.

    Here is the Video explanation 👇

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