Expand using suitable identities: (xy + yz)²

Solution:

Given, (xy + yz)²

Using standard identity: (a + b)² = a² + 2ab + b²

Here, a = xy and b = yz

(xy + yz)² = (xy)² + 2(xy)(yz) + (yz)²

= x²y² + 2xy²z + y²z²

✦ Try This: Expand using suitable identities: (ab - bc)²

Given, (ab - bc)²

Using standard identity: (a - b)² = a² - 2ab + b²

(ab - bc)² = (ab)² - 2(ab)(bc) + (bc)²

= a²b² - 2ab²c + b²c²

☛ Also Check: NCERT Solutions for Class 8 Maths Chapter 9

NCERT Exemplar Class 8 Maths Chapter 7 Problem 85(i)

Expand using suitable identities: (xy + yz)²

Summary:

Expanding (xy + yz)² we get, x²y² + 2xy²z + y²z²

☛ Related Questions:

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