How do you simplify $3^{- 2} + 2^{- 3}$ $3^-2+2^-3$ ?

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Answer 1 · 2017-12-21T08:47:32

$\frac{17}{72}$ $17/72$

Expression $= 3^{- 2} + 2^{- 3}$ $= 3^-2 + 2^-3$

$= \frac{1}{3^{2}} + \frac{1}{2^{3}}$ $= 1/3^2 + 1/2^3$

$= \frac{1}{9} + \frac{1}{8}$ $= 1/9 + 1/8$

$= \frac{8 + 9}{9 \times 8}$ $= (8+9)/(9xx8)$

$= \frac{17}{72}$ $= 17/72$

Answer 2 · 2017-12-21T09:58:33

As,

$a^{- m} = \frac{1}{a^{m}}$ $a^(-m)=1/(a^m)$

$3^{- 2} + 2^{- 3}$ $3^(-2) + 2^(-3)$

$↓ d d d d ↓$ $darrcolor(white)(dddd)darr$

$\frac{1}{3^{2}} d + d \frac{1}{2^{3}}$ $1/(3^2) color(white)(d)+ color(white)(d) 1/2^3$

As,

$3^{2} = 9, 2^{3} = 8$ $3^2=9,2^3=8$

$\frac{1}{9} + \frac{1}{8}$ $1/9+1/8$

Now find the LCM.... it is 72

$\frac{1 \times 8}{9 \times 8} + \frac{1 \times 9}{8 \times 9}$ $(1xx8)/(9xx8)+(1xx9)/(8xx9)$

$\frac{8}{72} + \frac{9}{72}$ $8/72+9/72$

Add

$\frac{17}{72}$ $17/72$

How do you simplify 3−2+2−33^-2+2^-3?