If `theta` is eliminated from the equations `x=a"cos"(theta-alpha)` and `y=bcos(theta-beta),` then `(x^2/a^2)+(y^2/b^2)-(2xy)/(ab)cos(alpha-beta)` is equal to (a)`sec^2(alpha-beta)` (b) `cos e c^2(alpha-beta)` (c)`cos^2(-beta)` (d) `sin^2(alpha-beta)`

Explanation

To solve the problem, we need to eliminate `theta` from the equations \( x = a \cos(\theta - \alpha) \) and \( y = b \cos(\theta - \beta) \), and find the value of the expression:

\[ \frac{x^2}{a^2} + \frac{y^2}{b^2} - \frac{2xy}{ab} \cos(\alpha - \beta) \]

### Step-by-Step Solution:

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