Question

The value of (7 power -1 - 8 power -1) whole power -1 -(3 power -1 - 4 power -1) whole power -1
​

Answer 1

Answer:

=56−12=44.

Step-by-step explanation:

Using law of exponents, a

−m

=

a

m

1

⇒ (7

−1

−8

−1

)

−1

−(3

−1

−4

−1

)

−1

=(

7

1

−

8

1

)

−1

−(

3

1

−

4

1

)

−1

⇒ (

56

1×8−1×7

)

−1

−(

12

1×4−1×3

)

−1

=(

56

8−7

)

−1

−(

12

4−3

)

−1

=(

56

1

)

−1

−(

12

1

)

−1

Again we will use a

−m

=

a

m

1

⇒(7

−1

−8

−1

)

−1

−(3

−1

−4

−1

)

−1

=(

56

1

)

−1

−(

12

1

)

−1

=56−12=44.

Answer 2

Given: $(7^{-1} - 8^{-1})^{-1} -(3^{-1} - 4^{-1})^{-1}$

Solution: Calculate the expression inside the parentheses and simplify exponents and square roots

= $(7^{-1} - 8^{-1})^{-1} -(3^{-1} - 4^{-1})^{-1}$

= $(0.143 - 0.125)^{-1} -(0.333 - 0.25)^{-1}$

= $0.018^{-1} -0.083^{-1}$

= $56-12$

= $44$