Evaluate 25³ − 75³ + 50³

Evaluate:

\[ 25^3 – 75^3 + 50^3 \]

Solution:

Rewrite the expression:

\[ 25^3 + 50^3 – 75^3 \]

Since, \[ 25+50=75 \]

Using identity:

\[ a^3+b^3+c^3=3abc \quad \text{when} \quad a+b+c=0 \]

Take \[ a=25,\qquad b=50,\qquad c=-75 \]

\[ 25+50-75=0 \]

Therefore, \[ 25^3+50^3-75^3 = 3(25)(50)(-75) \]

\[ = -281250 \]

Next Question / Full Exercise

Spread the love

Leave a Comment

Your email address will not be published. Required fields are marked *