Q13 of 40 Page 1

The value of is _____.

Sin20° cos70° + sin70° cos20°

= Sin (90 – 70) cos70° + sin70° Cos(90 – 70)


= Cos70°. Cos70° + Sin70° . Sin70°


= Cos270° + Sin270°


= 1


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If the equations kx - 2y = 3 and 3x + y = 5 represent two intersecting lines at unique point, then the value of k is___________.

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