**Find the values of**

(i) 7 sin 30° cos 60°

(ii) 3 sin^{2} 45° + 2 cos^{2} 60°

(iii) cos^{2} 45° + sin^{2} 60° + sin^{2} 30°

(iv) cos 90° + cos^{2} 45° sin 30° tan 45°.

**Answer :**

**(i)** 7 sin 30° cos 60°

= 7 ×½ ×½

= (7×1×1)/(2×2)

= 7/4

**(ii)** 3 sin^{2} 45° + 2 cos^{2} 60°

= 3×(1/**√**2)^{2} + [2×(1/2)^{2}]

= (3×½) + (2 × ¼)

= 3/2 + ½

= (3 + 1)/2

= 4/2

= 2

**(iii) **cos^{2} 45° + sin^{2} 60° + sin^{2} 30°

= (1/**√**2)^{2} + (√3/2)^{2} + (1/2)^{2}

= ½ + ¾ + ¼

= (2 + 3 + 1)/4

= 6/4

= 3/2

**(iv)** cos 90° + cos^{2} 45° sin 30° tan 45°

= 0 + (1/**√**2)^{2} × ½ × 1

= ½ × ½ × 1

= ¼

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